The author: Dr. Donald Perkins at the weather station but, sometimes, on expedition.

Llansadwrn (Anglesey)

Diary 2021

Logo: Llansadwrn Weather - Melin Llynnon, Ynys Môn

      Information on station times, averages & graphic icons. Click for pop-up explanation.     Types & rates of rainfall. Click for pop-up explanation.     Types of hail. Click for pop-up explanation.     Follow tywyddmon on Twitter

Times are GMT (UTC, Z). Observations at this station [ ] are 24-h 09-09 GMT, some others { } occasionally refer to other 24-h periods, extremes (first indications) are given in bold and are usually 21-21 GMT. When averages are referred to (.) compares with the last decade and [.] with the new 30-y climatological average [1991-2020]. All data are subject to verification and amendment.


January 2021

Wales was under COVID-19 tier four Lockdown.

January 1 - It was a bright start to the new year after overnight ground frost (-2.7C on the grass) with a light NNE'ly breeze. The 4.1C temperature at 0900 GMT for the obs did not feel too cold. Decided to continue the observations so here's hoping it will be a drier year than last with plenty of sunshine. Dates of first flowering snowdrop  in the garden in Llansadwrn winters 1996-2021. The first snowdrops of the winter/ spring 2021 to open in the garden.Pressure 1015 mb was rising with Atlantic-high 1032 mb to the SW. Altocumulus and cumulus 3 oktas were increasing with in particular cumulus developing to the west over the Irish Sea. There was snow on the Snowdonia Mountains lying at 1500 ft on the N-facing slopes of the Carneddau that I monitor, with remnants as low as 500 ft elsewhere. .Brief sunny spells in the afternoon (Scilly 8.2C Scolton 7.6C, Larkhill -7.3C Sennybridge -5.8C, Fylingdales 24.2 mm Rhyl 2.0 mm, Katesbridge 6.2h Aberdaron 2.2h Valley 1.5h) [Max 5.7C Min 0.1C Grass -2.7 Pptn 4.0 mm]. It was a wintry morning on the 2nd with a mixture of ice pellets (0522 GMT) followed by snow pellets and snow at 0830 GMT. The sky was overcast with a uniform grey cloud sheet and visibility was poor. It had been cold enough on the ground for water to freeze in troughs kept for birds, but there had been no air frost. The morning brightened and there were glimpses of sunshine through to the afternoon (Scilly 7.7C Scolton 6.4C, Eskdalemuir -7.9C Swyddffynnon -5.4C, Loftus 18.0 mm Aberdaron 4.6 mm, Dundrennan 6.2h Valley 4.0h) [Max 4.8C Min 0.8C Grass -4.0C Pptn 0.8 mm].

Snow on the mountains viewed from Llansadwrn across wet fields.

A fair morning on the 3rd with a light NE'ly breeze that strengthened during the morning. Mostly cloudy with not a lot of sunshine, but dry (Scilly 7.3C Scolton 6.5C, Loch Glascarnoch -9.1C Trawsgoed -2.6C, Chillingham Barns 18.2 mm Tredegar 7.2 mm, Tiree 5.9h Aberdaron 4.9h Valley 0.8h) [Max 4.8C Min 1.2C Grass -0.7C Pptn 0.1 mSome of the sparrows in our garden at Gadlys.m]. On the 4th in good visibility there was a sprinkling of fresh snow on the summits of the Snowdonia Mountains. The snowline remains at 1800 ft, above this line, that I observe each day, snow cover must be 50% or more. I estimated that there was a 30% cover above 1750 ft with some snow as low as 1000 ft near Cwm Idwal. A fine, but mostly cloudy day. About 10 sparrows are spending the winter in our garden this year. A few more than last year (Scilly 7.3C Scolton 6.2C, Loch Glascarnoch -8.5C Whitechurch -1.6C, East Malling 11.4 mm Sennybridge 0.4 mm, Tiree 6.0h Aberdaron 2.1h Valley 0.4h) [Max 4.6C Min 2.6C Grass -0.6C Pptn 0.1 mm]. No frost overnight, but the 5th began looking more wintry with snow showers moving across the mountain summits, but the 1800 ft snowline had not changed. Precipitation in sight was noted, we had recent light drizzle then a little rain, that's all. There was a trace deposition of coloured dust, the University of Athens SKIRON Model had forecast north African dust arriving from the east. Backward trajectory analysis of air arriving over Anglesey at 0900 GMT on 5 January 2021. Researched on the NOAA ARL Website. A light reddish-brown coloured Saharan dust was deposited around 0900 GMT. Backward trajectory analyses using the HYSPLIT model, courtesy of the NOAA/ARL website, indicated that parcels of air arriving over Anglesey at 0900 GMT originated from over the borders of Algeria and Tunisia. The most likely red route arriving at 4000 m AGL having taken an interesting and most unusual route over the Mediterranean, countries of south-east Europe, the Black Sea, Russia, the White Sea, north Finland (Lapland), the Gulf of Bothnia, southern Sweden, Denmark, the North Sea, northern England and the Irish Sea to arrive over Llansadwrn where it was washed out in rain. A fair day with a little sunshine at times (Magilligan 6.5C Usk 5.8C, Kinbrace -7.6C Tredegar -0.7C, Charsfield 11.0 mm Sennybridge 0.4 mm, St Athan 5.7h Valley 3.2h) [Max 4.8C Min 2.8C Grass 0.3C Pptn tr].

A very fine and bright morning on the 6th with cumulus clouds in the vicinity. Pressure was on 1025 mb with an Atlantic-high 1033 mb lying to the SW with a ridge towards the UK. There had been a light deposition of a coloured dust transported here on the easterly winds. A cold front to the NW was expected to move SE later. A short peak of sunlight 295 W m -2 at 1307 GMT tempted me outside to examine and clean out the bird nesting boxes. There had been 13 nests in the 23 boxes we have in use, 70% of the boxes had been used in some way in the past year. Uses included overnight roosting by bats, and one had a live mouse in residence making use of the nesting material (Ballywatticock 6.7C Scolton 6.0C, Loch Glascarnoch -12.3C Gogerddan -3.1C, Kenley 12.6 mm Libanus 0.4 mm, Aberdaron 7.1h Valley 5.4h) [Max 4.8C Min 1.7C Grass -1.3C Pptn 0.1 mm].

Evening sky as the sun set across the old cricket field at Gadlys.

It was a frosty morning on the 7th after clear skies at night with the moon rising over the mountains at 2130 GMT last evening. There had been heavy dew and this had frozen when the temperature on the grass dropped to -9.2C, lowest of the month. The fields were white with frost in the morning. There had been a fall of isolated star-like snow crystals, these evident on various surfaces including ice on water where they had been kept frozen. There was rime on the rims of the copper raingauge. The magic soon disappeared with freezing drizzle turning to slight rain when it all thawed. Snow was lying on the mountains above 1800 ft. We had heavy sleet from 1545 GMT falling at 15 mm/h at 1552 GMT (Scilly 8.0C Mumbles Head 5.8C, Redesdale Camp -9.5C Sennybridge -6.8C, Baltasound 12.6 mm Aberdaron 4.4 mm, Camborne 6.7h St Athan 5.0h Valley 0.2h) [Max 3.2C Min -1.8C Frost 14.7h Grass -9.2C Pptn 9.1 mm]. Dull and overcast on the 8th with poor visibility in rain and sleet. AWS temperature and solar radiation record for the 7 days to the 10th January 2021.The ground was very wet with some standing water in places after 9.1 mm of precipitation. Atlantic-high 1036 mb was lying to the W of Ireland with a ridge to Scotland, pressure here 1020 mb was rising. There had been snow pellets since midnight, the temperature was 2.2C (dewpoint 1.5C) at 0900 GMT and there was good chance of more ice precipitation. This came along in the shape of large flaked snow at 0940 GMT that began settling on grass, but was melting. There was another snow shower at 1320 GMT. The day was sunless and with a maximum of 2.7C it was the coldest day of the month (Scilly 6.9C Milford Haven 6.0C, Loch Glascarnoch -8.2C Gogerddan -3.0C, Loftus 24.2 mm Scolton 10.8 mm, Aldergrove 6.4h Aberdaron 0.7h) [Max 2.7C Min 0.0C Grass -1.4C Pptn 9.1 mm]. Turning colder overnight it was a cold and frosty morning on the 9th with icy conditions with an air minimum of -2.2C the lowest of the month. Snow pellets had fallen, the ground was hard and covered with white frost and the Stevenson screen door iced and frozen shut. You don't get many mornings like this in recent years. The AWS reading was -1.4C and by the time the screen was opened at 1000 GMT the thermometer inside read -0.3C. It was sunny with a blue sky and calm with moderate misty visibility. It was still sunny at 1300 GMT, hen cloud encroached with spells of slight rain or drizzle (Stornoway 8.5C Trawsgoed 6.2C, Eskdalemuir -11.9C Capel Curig -5.2C, Kinbrace 18.0 mm Capel Curig 0.8 mm, Wattisham 7.0h Aberporth 6.7h ) [Max 4.6C Min -2.2C Grass -8.1C Pptn 0.2 mm].

On the 10th snow was lying at 450 ft on the lower slopes of the Carneddau Mountains due SE of the weather station. When clear enough I have a good view 'across the water' or even 'across the river' was an old local expression. Reports from the mountains indicated a 'lot of snow' had fallen Today visibility was moderate with mist, but lifting rapidly so I got a decent view. Warmer at 4.2C, 97% RH, and no ice precipitation of any sort, rising to 6.5C during the day. It was a very dull day with spells of light to heavy drizzle, not amounting to anything in the raingauge (Achnagart 8.7C Hawarden 7.5C, Okehampton -5.8C, Tredegar -5.5C, Resallach 23.8 mm Swyddffynnon 0.6 mm' Waddington 2.9h Hawarden 0.9h) [Max 6.5C Min -1.4C Grass -3.0C Pptn tr]. On the 11th we were into a warmer airstream off the Atlantic. With pressure low 989 mb Norwegian Sea and high 1031 mb off Cap Finisterre a mild SW'ly airflow was the result. Pressure here 1016 mb was falling and we had another dull sunless day. There had been a significant snowmelt in warm rain on the mountains, the snowline raised to 2000 ft. Spots of rain gave way to heavier rain during the afternoon (Leuchars 10.9C Rhyl 10.0C, Baltasound -4.1C Tredegar 2.9C, Achnagart 47.2 mm Bala 17.2 mm, Lerwick 1.4h Hawarden 0.4h) [Max 8.7C Min 4.2C Grass 4.5C Pptn 13.5 mm]. After two sunless days the sky was clearing quickly on the morning of the 12th, brighter and a little colder again. Pressure 1015 mb was rising quickly in a ridge from high 1020 mb Iceland. A low 981 mb over the Baltic had associated cold fronts moving S over the UK. It was sunny to the north and wet to the south A fair day. At 2200 GMT the NE'ly breeze veered SW'ly with falling pressure and rising temperature in warm sector Atlantic air (Exeter 11.1C Cardiff 10.2C, Tulloch Bridge -5.9C Rhyl 4.5C, Okehampton 25.8 mm Swyddffynnon 21.4 mm, Boulmer 6.2h Hawarden 3.8h) [Max 8.2C Min 4.4C Pptn 4.8 mm]. There was continuous light rain from midnight on the 13th through the night to 06 GMT when it became moderate for a while. At 0900 GMT fog had developed and there was light rain the soil saturated. A dull, sunless and the wettest day of the year, so far (Shobdon 12.4C Usk 11.7C , Dalwhinnie -6.4C Capel Curig -0.6C, Ballypatrick Forest 28.4 mm Trawsgoed 21.6 mm, Kirkwall 1.8h Lake Vyrnwy 1.0h) [Max 9.4C Min 1.4C Pptn 21.5 mm]. On the 14th we were still in warm air the temperature at 0900 GMT 7.2C, pressure 1016 mb was rising quickly in a ridge. On the cold side of the frontal system lying over central England it was snowing in Scotland and NE England, From 1130 GMT the temperature began to fall, temperature range today 0.1C Min 7.2C Max 7.3C. At Gorwel Heights the range was, unusually, zero Min 7.3C Max 7.3C (Cardiff 11.9C, Drumnadrochit -1.0C, St Bees Head 31.8 mm, Swyddffynnon 16.8 mm, Thomastown 3.1h St Athan 2.0h Valley 0.5h) [Max 7.3C Min 7.2C Pptn 2.8C]. Weak sunshine through thin clouds exhibiting orographic waves.It was cold overnight on the 15th with an air minimum of -0.2C it was frosty for 0.7h, and a hard ground frost -5.3C. There was a white frost on the fields, concrete was dry, but there was ice on water. A brief red sky earlier turning cloudier at 0900 GMT with weak sunshine. Similar in the afternoon with glimpse of clear sunshine. Pruned the greenhouse vine, best done in January before the sap starts rising. There was moderate to heavy rain after 2200 GMT with rising temperature and falling pressure, the 24-h maximum 8.0C recorded at 0420 GMT (Scilly 10.2C Milford Haven 7.3C, Ravensworth -11.8C Hawarden -2.9C, Strathallan 11.8 mm Whitechurch 1.6 mm, Boulmer 6.1h Bala 2.4h ) [Max 8.0C Min -0.2C Grass -5.3C Pptn 10.4 mm].

The first 15-days were on the cool side with the mean temperature 3.6C (-1.9) & [-1.8] and wetter the Dwarf white Rhododendron in flower two weeks earlier in the garden than last year.72.7 mm (68%) & [70%] of the new averages. Not as wet as last year 2020 that had 101.3 mm (95%) & [98%] of new averages.

It was a fine and sunny morning on the 16th after a touch of ground frost. After heavy overnight rain the soil was 'soggy'. The temperature at 0900 GMT was 6.2C and with 97% RH visibility was moderate and misty. By 0930 GMT cumulus clouds were developing, but there were sunny spells into the afternoon. Took advantage of the saturated soil to pull out invasive weeds and brambles from the borders, they come out more easily when the soil is soggy (Gosport 11.4C Usk 10.5C, Redesdale -5.4C Lake Vyrnwy -0.9C, Achnagart 38.2 mm Mumbles Head 26.0 mm, Aberdaron 5.3h Valley 4.5h() [Max 8.7C Min 0.4C Pptn 0.4 mm]. There were showers of snow pellets after midnight and the morning of the 17th was bright with weak sunshine. A touch of ground frost, but no white frost seen. Mostly cloudy with just weak sunshine and a few glimpses of clear sunshine in the afternoon (Scilly 9.8C Milford Haven 9.0C, Aboyne -1.4C, Achnagart 15.6 mm Rhyl 2.8 mm, Shoeburyness 5.6h Hawarden 0.3h) [Max 6.6C Min 2.5C Grass -1.7C Pptn tr]. After a dry night the 18th turned out to be very wet. Slight rain had just started at 0900 GMT. Pressure 1021 mb was falling with Atlantic-lows 991 mb to the SW and NW, there was a cold front lying over northern England. Light rain from noon becoming heavy at 2200 GMT (Scilly 11.1C Gogerddan 10.1C, Frittenden -2.2C, Achnagart 15.4 mm Capel Curig 11.2 mm, Leuchars 4.3h Hawarden 0.3h) [Max 9.1C Min 3.1C Grass 0.3C Pptn 31.5 mm] [Gorwel 29.4 mm]. Rain continued moderate to light through the night and by the morning of the 19th it had turned to intermittent drizzle and had accumulated 31.5 mm at 0900 GMT, the largest fall of the month of 18 h duration At Gorwel in Llanfairfechan 29.4 mm had fallen. Heavy rainfall in Wales 72 h up to 06 GMT on the 21 Jan 2021.Pressure 999.8 mb had fallen with complex low 990 mb (Storm Cristoph) W of Ireland. A warm front was lying over N Wales and N England. Today's maximum 10.0C highest of the month. Light to moderate rain most of the day into the night (Charsfield 12.5C Hawarden 11.4C, Aboyne -6.5C, Capel Curig 76.6 mm, Stornoway 4.2h Valley 0.1h) [Max 10.0C Min 5.7C Pptn 21.8 mm] [Gorwel Max 10.6C 28.6 mm]. Another very wet day on the 20th there was a large pool of water on the old cricket field at Gadlys. It does not happen very often, but when it does the soils hereabouts are saturated. It had been windy overnight 30 mph at 0251 GMT. At 0900 GMT 21.8 mm had accumulated over 18h duration. Pressure 982 mb was still falling with a cold front over Anglesey associated with low 978 mb N North Sea. The temperature had fallen from 9.8C to 6.2C. Raining heavily 4 mm was to fall in the next hour, with a burst of 14 mm/h at 0944 GMT. A very dull sunless day with mist visibility was very poor. The River Bollin at Wilmslow, Cheshire had burst its banks. There was snow there in the evening. Heavy snow had fallen during the day on Cairngorm Mountain and turning colder would later fall in Snowdonia (Bude 12.1C St Athan 11.6C, Dalwhinnie -5.9C Mona 5.9C, Capel Curig 87.8 mm, Tiree 2.8h Valley nil) [Max 6.2C Min 6.2C Grass 6.3C Pptn 22.5 mm 19h duration][Gorwel Max 6.6C Min 6.6C Pptn 34.2 mm 18h duration]. On the 21st at 0900 GMT the total rainfall over the past 24-h was 75.8 mm over 55h duration that's 14 mm/h. At Gorwel Heights over the same period 92.2 mm had fallen over 48h duration that's 1.9 mm/h. At Capel Curig in the 72h to 06 GMT 178 mm had fallen with 117 mm at Bala and 110 mm at Lake Vyrnwy (graphic above left). Amber warnings for rain and 200 flood warnings had been issued. On Anglesey large areas of Malltraeth Marsh were flooded. At Lymm near the River Mersey homes were flooded and at Rosset family and their dogs had to be rescued from rising water by helicopter. Another 2000 homes in Dimsbury and Ruthin and Bangor-on-Dee were in danger of flooding. Shops had to shut after a retail park in Rhyl was flooded. Sainsbury's was forced to close its doors after the deluge which has submerged the car park. It did stop raining and during the afternoon the sky began to clear there was a little sunshine, but the temperature dropped from 5.6C at 1537 GMT to 1.3C at 1847 GMT (Manston 9.6C Usk 8.4C, Tulloch Bridge -3.8C, Fyvie Castle 29.4 mm Gogerddan 19.2 mm, Hawarden 6.2h Valley 1.7h) [Max 5.6C Min 1.3C Grass -0.6C Pptn 0.3 mm].

A fine and frosty morning on the 22nd, there was a light white covering on grass made up of ice crystals and frozen dewdrops, the grass minimum thermometer read -5C, and there was ice on water, the soil was frozen hard. Frost on grass and thermometer reading -5C.At 0900 GMT the sun had just risen above the mountain cloud on the Carneddau. Yellow Crocus in flower in our garden at Gadlys.A little misty with moderate to good visibility, but clear to see the snowline at 2000 ft on the mountains. Pressure 992 mb was rising with low 961 mb S Norway. Polar air in circulation from N Scandinavia brought showers through the North Channel on to the North Wales coastline. Cloudier around noon then some sunshine in t he afternoon. There were ice crystals (h1) floating around in the air about 10 pm. Skewen in South Wales had been badly flooded when after heavy rain there was a 'blow-out' of water from an old mineshaft. Villagers face a seven mile diversion for at least 18 months after Storm Christoph destroyed the 1800s Llanerch Bridge in Denbighshire on the main route between Trefnant and Tremeirchion linking to the A55. Sainsbury's in Rhyl was partially underwater () [Max 5.9C Min 0.7C Grass -5.0C Pptn 0.6 mm]. On the 23rd pressure 996 mb was rising with lows 988 mb off Brest, France, and 974 mb SE Norwegian Sea.Very small graupel or snow pellets had fallen. It was a bright, cold and frosty morning with a light WNW'ly breeze. Very small graupel or snow pellets had fallen around snowdrops.Overnight the grass minimum recorded -8.0C and the air temperature at 0815 GMT was -1.6C during 5.7h below zero. The cold plunge from Polar regions continued with shower troughs over the UK. We had a shower of very small graupel (snow pellets) too light in mass to mark the hailpad, but captured landed on the leaves of a dwarf Rhododendron. It was mostly sunshine here in the afternoon with the temperature rising to 5.8C at 1 pm, but there was a snow shower at Gorwel Heights where the temperature struggled to reach 2.9C (Scilly 7.7C Cardiff 6.6C, Spadeadam -0.9C, Braemar -7.7C Sennybridge -5.4C, Rhyl 17.2 mm, Boulmer 7.0h St Athan 5.8h Valley 3.1h) [Max 5.8C Min -1.6C Grass -8.0C Pptn 0.3 mm]. Another cold morning on the 24th with early showers of snow pellets and snow, less than 50% cover at 0900 GMT. Snow was lying at 1000 ft on the mountains, a 30% cover at 500 ft and there was ice precipitation at sea level in places including Rhosneigr. Fine and bright with snow flurries in the afternoon. There was a burst water main on the hill at Gorwel, Llanfairfechan. There another large flaked snow flurry at midnight (Scilly 7.5C Mumbles Head 4.7C, Tn Lake Vyrnwy -1.2C, Dalwhinnie -11.4C Sennybridge -5.3C, Milford Haven 20.8 mm, Boulmer 7.3h St Athan 2.1h Valley 1.5h) [Max 2.9C Min -0.8C Grass -5.5C Pptn 0.7 mm].

Clouds and snow cover Carnedd Llewelyn.Flurries of snow pellets and snow after midnight on the 25th, but it was a very fine and sunny morning though cold. At 0900 GMT the temperature -0.2C (dewpoint -0.6C) after 10.3 h of air frost (minimum -1.9C). There was a covering <50% of snow pellets (grass minimum -7.4C), but little evidence of snow here. Light snow was lying at 500 ft on the Carneddau, with some ice precipitation as low as 250 ft. Little in the way of cloud in the sky but signs of cumuli over the mountains building up a little. Visibility initially poor with some mist, but improving through the morning. The afternoon kept mostly sunny the temperature rising to 6.7C at 1249 GMT (Scilly 8.1C Milford Haven 7.5C, Tx Sennybridge 1.4C, Katesbridge -10.4C Sennybridge -9.7C, Resallach 16.2 mm Scolton 12.6 mm, Shoeburyness 8.1h Valley 6.3h) [Max 6.7C Min -1.9C Grass -7.4C Pptn 1.9 mm]. The 26th reverted to poor weather with overcast skies, ragged low cloud and slight rain. Visibility was moderate to good and the slight rain soon ceased. Some remnants of the falls of snow pellets on the grass, The day kept dull and sunless. The number of COVID-19 deaths in the UK sadly had reached 100,000, more than the number casualties that occurred in WWII blitz (Scilly 11.0C Milford haven 9.5C, Dalwhinnie -9.5C Sennybridge -4.2C, Scilly 15.6 mm Mumbles Head 14.8 mm, Lerwick 6.0h Valley nil) [Max 8.4C Min -0.2C Grass -5.1C Pptn 0.6 mm]. The 27th began with thick shallow fog, visibility decreasing to 100 m at 0900 GMT, with the sky obscured. By 10 GMT the fog began lifting slowly, but it was a poor day that was sunless. There was light to moderate ran from 1800 GMT sometimes heavy around midnight when the wind, which had backed and gone around the compass in five hours, strengthened force 5/6 (Scilly 11.3C Whitechurch 10.8C, Baltasound -6.6C Hawarden 2.6C, Millport 9.2 mm Aberdaron 9.2 mm, Lerwick 4.3h Lake Vyrnwy 0.1h) [Max 9.7C Min 3.7C Grass 2.1C Pptn 21.6 mm]. Heavy rain at 02117 GMT fell at up to 11 mm/h and the temperature had been rising and reached 9.5C at 0222 GMT. The air minimum was 7.3C, the highest of the month The barometer bottomed at 998 mb at 0420 GMT on the 28th, as the rain eased towards 06 GMT there was moderate fog and at 0900 GMT it had stopped raining, but visibility was still very poor. Wet overnight with 21.6 mm accumulated over 13 h duration. The wind had moderated and soon the sky cleared a little with weak sunshine putting in an appearance, even a glimpse of clear sunshine. We were in a warm moist SW'ly airflow with pressure on 999 mb rising. A curlew flew over the weather station and there was a buzzard in the vicinity. The usual pheasant was picking around under bird feeders and a red squirrel was at one of the feeding boxes. It was dull again by 11 GMT, but kept dry until 3pm when the fog developed with light rain (Pershore College 14.2C Usk 13.8C Gorwel Heights 12.2C, Braemar -6.8C Valley 0.0C, Killowen 33.2 mm Lake Vyrnwy 30.2 mm, Lerwick 4.1h Bala 0.8h) [Max 9.8C Min 7.3C Pptn 3.5 mm].

On the 29th the sky had been clearing since dawn and it was a fine and bright morning with moderate misty visibility. A pied wagtail put in a brief appearance. The fine start did not last as cloud increased and slight rain and drizzle developed (Gosport 12.1C Cardiff 11.6C, Lerwick -4.6C, Dyce 19.8 mm Capel Curig 14.8 mm, Tiree 6.3h Aberporth 1.9h) [Max 8.6C Min 6.3C Pptn 1.6 mm].

Snow on the Carneddau Mountains outlines enhanced by windblow.

A wintry day on the 30th, it was snowing at 1000 ft at Ogwen and was sleeting here in a strong ENE'ly wind. Light snow was at 500 ft on the mountains and a bit lower by afternoon. There had been a constant roar in the tall trees most of the night, we were somewhat sheltered from it in the garden, but the obs at 0900 GMT was unpleasant. Pressure was on 995 mb with low 974 mb over the Celtic Sea. Windblown snow enhances topographic features on the Carneddau Mountains.Windblown snow enhances topographic features on the Carneddau Mountains.The afternoon was drier with bits and pieces of sleet and snow on the still strong wind (Culdrose 11.1C Pembrey Sands 8.0C, Tx Balmoral -0.2C Lake Vyrnwy -0.1C, Altnaharra -10.1C Lake Vyrnwy -0.1C, Plymouth 26.8 mm Aberdaron 18.0 mm, Tiree 6.4h Aberdaron 3.9h Valley nil) [Max 3.3C Min 2.4C Pptn 0.6 mm]. There was a red sky briefly after dawn on the 31st, but the sky was overcast at 0900 GMT with moderately high cloud. Pressure on 1002 mb was falling quickly with low 976 mb W of Ireland. Ground frost overnight -4.6C with ice on water. It stayed cloudy all day with some weak sunshine at times no clear sunshine maximum 4.1C at 1515 GMT, and it was dry, the first and only dry day of the month. Windblown snow resulted in the topographic features on the Carneddau Mountains being enhanced in the photos taken today (Scilly 11.4C Valley 4.2C Llansadwrn 4.1C Gorwel Heights 3.4C, Braemar -13.0C Hawarden -3.6C, Culdrose 18.4 mm Whitechurch 6.0 mm, Loch Glascarnoch 6.7h Valley nil ) [Max 4.1C Min 0.3C Grass -4.6C Pptn nil].

The month ended with a total of 180.6 mm of rainfall (169%) & [175%] of the new averages largest since 2008, the 7th wettest in Llansadwrn since 1928. It had been wintry the mean temperature 4.1C lowest since 2010 and the 6th lowest in station records since 1979. It was a dull month, sunshine recorded at RAF Valley was 41.1h (80%) & [73%] of the new averages, lowest since 2019 and 18th lowest on the Anglesey record since 1931, there were 13 sunless days..

 

Home page Site map  Latest entry  Home page Site map  Latest entry

February 2021

Wales was under COVID-19 tier four Lockdown...

February 1 - grey skies, cold, but fine and dry, and by 10 am becoming a little brighter. Pressure 997 mb was rising with low 991 mb Scilly in a complex chart. I find the MetO analysis charts more complex and difficult to read these days, no doubt the result of super computers and satellite images. At present the weather is complex forecasters contending with rapidly changing alternating cold polar and warm moist Atlantic airflows. It seems a while since we have had settled weather. I needed a dry spell at the beginning of a month to service the lysimeter. For while the percolate has been coloured, and of late the colour has been stronger. I fill it with the local soil that is slightly acidic, and with 2020 the wettest year on record, and a wet January the soil has had enough and become gleyed. Despite spiking through drainage has become impeded. The aim is to keep the soil moist, but the recent conditions the soil has been waterlogged and under the anaerobic conditions iron compounds in the soil became reduced and leached out. So today was lysimeter service day. The grass top was removed and the under layer of gravel removed and washed. Drainage through the outlet at the base and pipe to the receiver was checked before replacing the washed gravel. I cut out a fresh 30 cm diameter nice piece of turf from the lawn, trimmed the depth to size and placed it in the lysimeter tank. It was ready for use again before the end of the day. You can read about how I constructed and set up the lysimeter back in May 1996 here. (Scilly 11.3C Gorwel 7.0C Porthmadog 6.8C Llansadwrn 6.3C, Altnaharra -10.5C Lake Vyrnwy -1.8C, Camborne 9.4 mm Milford Haven 2.2 mm, Waddington 7.8h Aberdaron 4.8h) [Max 8.7C Min -0.1 Grass -3.0C Pptn 7.3 mm]. An overcast day on the 2nd with low cloud and very poor visibility. Pressure 989 mb had fallen with low 973 mb over Shannon, Ireland. There was an occluded front over the Irish Sea and N Wales. The wind had veered E to SE between 04 and 06 GMT. There was a band of rain across the UK with strong winds to the north Malin Head gusting 54 mph and Bridlington 44 mph. The day was sunless (Cardiff 14.2C, Altnaharra -12.1C, Capel Curig 35.6 mm, Lerwick 4.0h St Athan 0.5h) [Max 10.1C Min 1.7C Pptn 9.8 mm]. The 3rd began brighter after heavy rain at 0145 GMT, the sky to the SE looked lighter, but visibility was poor in mist Pressure 992 mb was rising, the slow-moving low near Shannon 981 mb and the occlusion was over the North Channel. Improving through the morning the afternoon was sunny (Rostherne 11.3C Hawarden 10.5C, Altnaharra -3.9C, Ballypatrick Forest 45.6 mm Capel Curig 16.2 mm, Aberdaron 5.6h Valley 3.4h) [Max 8.6C Min 8.1C Pptn 2.8 mm]. The sky was briefly red to the E early on the 4th, at 0900 GMT the temperature was 7.6C and visibility was just good and a little hazy. There had been a little rain overnight, the morning though mostly cloudy had some weak sunshine. The low of yesterday was now 997 mb over N Ireland. Frontal cloud was to the north of here and the afternoon was sunnier as the sky cleared. Mist and fog central and SE England (Porthmadog 11.4C Gorddinog AWS 11.2C, Altnaharra -3.1C, Logan Botanic Garden 51.0 mm Cardiff 7.6 mm, Aberdaron 7.3h Valley 4.4h) [Max 10.9C Min 6.0C Pptn 2.8]. Not much in the way of cloud on the morning of the 5th with a sunny morning. Pressure was on 1005 mb with the filling slow-moving low 1001 mb near Malin Head. Woodpeckers were drumming in the wood and jets from Valley were in the vicinity flying towards the mountains. Again mist and fog central, E and SE England. The afternoon was disappointing, it had turned cloudy and slight rain developed turning heavier by 1430 GMT (Kew Gardens 11.7C Rhyl 9.5C Gadlys Gardens 8.1C, Shawbury -0.3C, Tyndrum 46.6 mm Porthmadog 8.6 mm, Wattisham 5.8h Valley 2.9h) [Max 8.1C Min 4.3C Pptn 15.0 mm]. Rain overnight heavy just after midnight on the 6th and a dull morning with low cloud and mist. Pressure 1009 mb was rising, but the sky was slow to clear. It was a cooler 3.9C at 0900 GMT and there was an ESE'ly breeze. It was later in the afternoon before there was any sunshine () [Max 5.5C Min 2.7C Pptn tr].

Snow showers on the Carneddau Mountains in the aftrnoon.

A breezy morning on the 7th with a hint that the sky was clearing, the 2.1C at 0900 GMT felt very cold in the E'ly wind. Pressure was on 1012 mb with a high 1041 mb over the Norwegian Sea and Atlantic-low 992 mb lying to the south-west. This was resulting in a blast of Continental/ Polar air across the UK. It was snowing in SE England at Ramsgate, NE England and E Scotland. Here snow showers across the mountains in the afternoon, snow pellets were reported at Gorwel in Llanfairfechan. Some sunshine then turned dull with ice precipitation 'on the wind' later in the afternoon (Scilly 7.2C Pembrey Sands 5.1C, Braemar -2.7C Whitechurch -1.2C, St Catherine's Point 11.4 mm Scolton 6.4 mm, Stornoway 3.9h Aberdaron 2.5h) [Max 3.4C Min 2.0C Pptn tr]. A fine and bright morning on the 8th after light showers of snow pellets around 08 GMT. With 5 oktas of cumulus clouds there were crepuscular rays wen looking towards the mountains. Visibility was moderate with haze, but broken snow could be seen around 2250 ft with snow patches at 2000 ft with remnants even lower. Expected temperature on the summits today -7C with a wind chill of -18C. There is a huge amount of snow on Cairngorm Mountain ski area this year. Currently blown snow is covering the funicular railway track in places even though it is on stilts (currently not used due to structural issues) and ski runs. It is all closed of course, as is Snowdonia, because of coronavirus lockdown regulations. Some sunny spells in the afternoon, showers from the east off Red Wharf Bay reached here at 1710 GMT with a fall of very small snow pellets or graupel that covered the ground. It was loose and powdery as the surface ground temperature was below zero, it did not melt and remained the same until next day (Scilly 4.5C Milford Haven 4.1C, Fyvie Castle -7.8C Lake Vyrnwy -2.6C, Houghton Hall 4.6 mm Scolton 1.0 mm, Dundrennan 7.6h Hawarden 1.6h) [Max 2.4C Min 0.5C Grass -1.3C Pptn 1.0 mm]. A cold morning on the 9th, but bright with not a lot of cloud. Pressure was on 1010 mb, the jetstream is currently well south of us, usually to the north, it was snowing widely in SE England an elsewhere. The E'ly wind was still with us with a severe wind chill effect on the mountains of about -20C. Here at 0900 GMT -0.5C with a wind chill of about -3C soon penetrating my mittens during obs. The loose powdery snow pellets that fell yesterday evening, plus some more were on the ground, nicely crunchy underfoot. There was some lying at sea level in places as well including Rhosneigr beach. Snow pellets, or other forms of hail on the ground even if covering the ground, do not count as snow (lying) recorded at morning observations. It is very light in weight and when melted the volume is small, it also does not mark the hailometer. A red squirrel was at a nearby feeding box not taking a lot of notice of me doing my rounds of the weather station and garden, too busy eating monkey nuts and hazel nuts. Continuing cold, the maximum 1.7C in the afternoon despite the sunshine. Anglesey (Valley 7.9h) had the most sunshine in the UK today. There was a snow shower between 1335 and 1405 GMT and very large flakes fell at 1455 GMT for a while (Scilly 5.3C _Porthmadog 3.9C, Altnaharra -16.7C Tredegar -3.9C, Charsfield 7.2 mm Tredegar 0.6 mm, Valley 7.9h) [Max 1.7C Min -1.5C Grass -4.5C Pptn tr].

A very fine, sunny and cold morning on the 10th with the ground hard and frozen, there were remnants of icy precipitation in shady places. Very little cloud, just 1 okta, mountains and to the NE over Red Wharf Bay. We still had the easterly wind. Pressure 1019 mb was rising quickly with high 1029 mb, between Iceland and Scotland heading for the Norwegian Sea, with ridge to N France. The North Sea was covered with open cell marine convective clouds heading for the east coast. There was snow on the ground from N Scotland to Kent. There was a good covering of snow on the Snowdonia Mountains with cornices developed on cliffs due to the easterly wind (Scilly 5.0C Usk 4.5C, Altnaharra -17.1C Whitechurch -6.2C, Craibstone 4.4 mm St Athan tr, Kirkwall 7.7h Valley 7.1h) [Max 3.5C Min -2.1C Grass -6.5C Pptn tr]. Cloudier on the morning of the 11th, cold with an overnight minimum of -2.6C in the Stevenson Screen, and -7.3C was recorded by the grass minimum thermometer. The temperature under bare soil at 5 cm depth was 0.3C this rising down the profile reaching 6.3C at 100 cm deep, still above the 5.6C (42F) 'plant growth' temperature. Soil at 50 cm deep was 4.8C too low for growth. Conditions are such that plants in the garden soil are suffering physiological wilt, including my leeks and chard. The freeze drying conditions means that fallen leaf material on the ground in the wood is very dry, as must be leaf litter and surface vegetation on mountains and moorlands not covered in snow. There have been fires on Bodmin Moor in recent days and a large one on Dartmoor today. Fires can move on moors very rapidly in wind, usually the vegetation on wet peat will regrow, but in dry summers when the peat is dry it also can burn and for weeks damaging the ecology (Bridgefoot 5.4C Valley 3.2C, Braemar -23.0C Tredegar -6.5C, Balmoral 4.8 mm Llysdinam 0.2 mm, Leeming 8.9h Hawarden 4.5h) [Max 1.8C Min -2.6C Grass -7.3C Pptn nil]. On the 12th extreme downslope winds off the Carneddau overturned a lorry travelling east on the A55 near Aber, the road was closed with traffic diverted. There were gusts of 46 mph at Gorwel Llanfairfechan and David Lees's Gorddinog AWS station 52 mph just after noon, and 58 mph in the evening. At Gorwel slates were blown from roofs. At the weather station the wind was very turbulent at times bringing down a lot of soot from a chimney. A sunny afternoon. Pressure was still high 1045 mb S Norway and with low 952 mb W of Ireland the easterly continued overnight. A change was on the way with frontal systems stacked up to the SW that would introduce much warmer Atlantic air (Scilly 6.7C Valley 5.4C, Kinbrace -15.4C Lake Vyrnwy -4.8C, Leuchars 7.0 mm Wales nil, Kinloss 7.9h Valley 6.5h) [Max 4.5C Min -0.3C Grass -3.3C Pptn tr]. A dull and cold morning on the 13th with air and ground frost overnight. A brief reddish coloured sky early. The surface of bare soil was dry and frozen, there was a shower of snow grains, small angular translucent hard ice grains that could be heard hitting the ground. Later there was a flurry of small snow flakes. It was windy in Llanfairfechan with gusts of 43 mph at 0112 GMT at Gorwel Heights and 58 mpg at 0847 GMT at Gorddinog off the mountains, here a light ESE'ly (Scilly 10.1C Valley 4.7C, Tx Pennerley -3.1C Lake Vrnwy -2.8C, Tn Loch Glascarnoch -6.5C Tredegar -5.6C, Culdrose 11.4 mm Milford haven 4.0 mm, Wattisham 6.7h Aberporth 0.9h) [Max 9.0C Min -1.7C Grass -5.3C Pptn 2.8 mm]. On the 14th the sky was overcast it was very windy and warmer the temperature at 0900 GMT 8.3C. The SSE'ly wind was blowing force 5/6 and there was a fine drizzle with poor visibility. Pressure 1013 mb was falling rapidly with a frontal wave low 976 mb off SW Ireland. With a Norwegian high 1046 mb isobars were tight over Britain, at Gorddinog a gust of 53 mph at 0900 GMT and at South Uist there was a gust of 70 mph. The temperatures in Llanfairfechan at 0143 GMT was 12.1C. The wind strengthened to strong to gale force in the afternoon with gusts of 61 mph at Valley. Wet in S Wales, sunless day (Armagh 13.3C Capel Curig 11.C, Dalwhinnie -4.9C Lake Vyrnwy -2.8C, Whitechurch 40.4 mm, Thomastown 1.9h) [Max 11.9C Min 0.8C Pptn 2.1 mm]. A fair morning on the 15th, bright and breezy with some weak sunshine at first then breaking through the thin cloud some sunny spells.. There was a mild wedge of air off the Atlantic moving eastward. No overnight frost anywhere it seemed, at 0900 GMT 8.7C this rising to 10.8C by 1332 GMT. The moderate visibility improved a little, just good enough to se that most of the mountain snow had disappeared leaving a few snow patches around 2750 ft and at Don's dyke. Temperatures in Llanfairfechan in the afternoon, Gorwel Heights 12.6C 1530 GMT, then Gorddinog AWS 12.8C at 2330 GMT (Kew Gardens 13.9C Hawarden and Gorwel Heights 12.6C Gadlys Gardens 10.8C, Albemarle 0.1C, Wych Cross 14.4 mm Tredegar 4.8 mm, Wellesbourne 5.0h Valley 2.9h) [Max 10.8C Min 7.8C Grass 5.9C Pptn 2.2 mm].

The first 15-days were wintry with a mean temperature 4.2C (-1.7) & [-1.4] of averages. Precipitation (15.0 mm on the 5th), but some hail and snow at times, totalled 43.5 mm (42%) & [48%] of averages. More sunshine that the whole of January.

The 16th began again mild, but breezy and fairly dull although there were signs of the cloud breaking up and it was sunny at 10 GMT. A heavy shower of rain and ice pellets at 1452 GMT (Myerscough 13.6C Cardiff 12.5C, Cassley 1.2C, Achnagart 31.6 mm Tredegar 21.8 mm, Kinloss 7.9h Aberdaron 4.9h) [Max 10.7C Min 8.2C Grass 6.4C Pptn 8.1 mm]. A fine, but breezy morning on the 17th as a result the 7.4C temperature at 0900 GMT felt quite chilly. Visibility was poor in haze at first. Some weak sunshine at first, light showers in the middle of the day then some sunny spells in the afternoon. Sparrows were occupying the penthouse nest site on the house and interest being shown in the terrace nest box, looks like they were nest building. There are about 5 pairs here this year. Increasingly windy in the evening strong to gale force from 2300 GMT as the barometer began to fall rapidly (Pershore College 13.3C Cardiff 11.6C, Fyvie Castle -0.7C, Balmoral 32.8 mm Libanus 24.6 mm, Aberdeen 6.5h Valley 3.9h) [Max 10.3C Min 6.7C Pptn 7.8 mm]. It was a rough night with gusts of 48 mph at 0018 GMT, Gorwel Heights recorded 57 mph at 0315 GMT when the temperature had reached 11.8C, and 58 mph recorded at Valley between 02 and 04 GMT. There was heavy rain just before 05 GMT all down to a cold front passing over between 0500 and 0700 GMT. There was a modest temperature drop of 4C to a minimum of 3.9C recorded on the 18th at 0646 GMT. A breezy morning , with some glimpses of sunshine, the duller afternoon had fewer (Shoeburyness 11.6C Cardiff 10.9C, Banagher Caugh Hill 0.7C, Achnagart 37.4 mm Capel Curig 19.4 mm, St Athan 6.2h) [Max 9.2C Min 3.9C Grass 2.8C Pptn 1.4 mm]. The 19th began with strong to gale force S'ly wind and poor visibility in mist and rain. At 0900 GMT pressure 996 mb was falling with a low to the NW 955 mb covering a very large area of the North Atlantic from Nova Scotia to the Canary islands. There was a warm front lying over the Irish Sea the temperature 9.2C. Capel Curig had had a gust of 71 mph and Gorwel Heights 58 mph. There was a MetO amber warning for rain affecting S Wales and several flood alerts had been issued. Light to moderate rain, the wind moderating in the afternoon, turned moderate to heavy in the evening. Wet in S Wales and the Lake District (Edinburgh Botanic Gardens 13.2C Rhyl 12.7C Gadlys Gardens 11.4C, Westonbirt 1.0C, Keswick 65.4 mm Whitechurch 55.4 mm, Kinloss 1.6h Valley nil) [Max 11.4C Min 4.3C Pptn 18.8 mm 16h duration].

Much the same on the 20th, the morning was very wet and the wind that had moderated was strengthening again. Pressure 993 mb was falling quickly with a frontal-wave low 973 mb Shannon. There was a gale warning in force for the Irish Sea and was so just after noon at Valley gale 8 with gusts of 55 mph, the Scilly Isles had 58 mph. The MetO amber warning was still in force, there was flooding in parts of S Wales. The River Towy burst its banks in Carmarthen and the R. Tywi near Capel Dewi. Roads near Lampeter were underwater and the R. Usk had burst its banks in Crickhowell and Llangattock in Powys. At Llyn-y-Fan, Carmarthenshire 127.6 mm was recorded. Gales in the afternoon with gusts of 42 mph here, 63 mph in Llanfairfechan at Gorwel and Gorddinog (St James Park 15.6C Gorwel Heights 13.8C Gorddinog AWS 13.2C Capel Curig 12.8C, Altnaharra -0.3C, Libanus 70.0 mm, Shoeburyness 6.0h Valley nil) [Max 12.5C Min 9.1C Pptn 5.8 mm]. Narcissi in flower in our garden at Gadlys.Much improved on the 21st with a drying S'ly breeze the sky with cirrostratus was clearing to cumulus and for a while lenticular altocumulus. Visibility was good, though a bit hazy. A large number of twigs had been blown off the trees and garden furniture turned over. Fine and sunny, weak at first a few clear sunny spells in the afternoon (Weybourne 15.9C Gorwel Heights 13.1C Rhyl 12.6C, Cassley 2.1C, Achnagart 13.8 mm Pembrey sands 7.4 mm, Kirkwall 6.9h Valley 2.2h) [Max 12.1C Min 12.3C Pptn 0.7 mm]. The 22nd began fine and bright with a light SW'ly breeze. A few cumulus clouds over the mountaintops and a few more could be seen in the far W over the Irish Sea and to the NE towards Cumbria. Pressure was rising and it remained sunny all day. From 18 GMT the S'ly the wind strengthened (Hawarden 13.4C, Tx Dalwhinnie 6.7C Lake Vyrnwy 9.1C, Derrylin Cornahoule -1.3C, Libanus 11.6 mm, Prestwick 8.0h Aberdaron/ Valley 7.6h) [Max 11.1C Min 6.3C Pptn 0.1 mm]. Pressure had started to fall just after midnight on the 23rd and by 0900 GMT it was 1009 mb. The MetO had issued a yellow warning for both wind and rain for North Wales. Wind had strengthened through the night and in the morning was blowing force 8 to 9 in places in North Wales. Capel Curig reported a gust of 76 mph and n Llanfairfechan 64 mph at Gorwel Heights and 61 mph at Gorddinog. The wind was relentless, wind run at Gorwel for the day was 470 miles. The storm (not named!) caused a lot of damage in Llanfairfechan to greenhouses and slates and ridge tiles were removed from the roofs of several properties. It was also very wet, in Llansadwrn 50.6 mm was recorded falling in the 24h to 0900 GMT, rain for 23h duration. There was standing water and a pool on the Gadlys old cricket field and the 19th century haha was filled with water. Power cuts hit three areas of Wales, with an emergency shutdown in Conwy triggered in one place after high winds snapped an electricity pole. Houses in the Dinorwic and Llanberis areas, along with those in Caernarfon and Bangor were without power for a time (Rhyl 15.0C Gorwel Heights 14.3C Gorddinog AWS 14.0C, Kielder Castle -0.6C, Keswick 59.0 mm Capel Curig 36.2 mm, Shoeburyness 8.9h Bala 0.9h) [Max 11.2C Min 6.4C Pptn 50.6 mm]. The 24th was another wet day beginning overcast with very poor visibility in drizzle and mist, but the wind had moderated overnight. Pressure 1014 mb, however, was set to rise with low 972 mb NW of Scotland moving N the warm southern air over the Irish Sea being replaced by something cooler, a high north-east of the Azores seemed likely to extend a ridge towards the UK. Not today, a minor cold front resulted in a temperature fall from 9.8C at midnight to 8.9C at 0900 GMT that was the day's maximum, on to 7.4C at 1930 GMT. There was light rain at first turning moderate for a while in the afternoon, the pool of water standing on the old cricket field remained there all day. Sunless with zero evaporation recorded by M Piche's evaporimeter (Santon Downham 18.4C Hawarden 14.9C, Loch Glascarnoch 4.1C, Capel Curig 49.6 mm, Manston 7.0h) [Max 8.9C Min 8.7C Pptn 9.8 mm].

View N from Gadlys, Llansadwrn.

In complete contrast to yesterday the 25th the sky had cleared and the morning was fine and sunny. The temperature was 6.1C with 97% relative humidity visibility was moderate and misty. The ground was very wet and muddy, but in a light WSW'ly it was drying slowly. Pressure had risen to 1025 mb with the ridge from Azores high 1037 mb extended to Cornwall. Soon a few fair weather cumulus clouds developed, the afternoon was sunny with fine views looking N from near the weather station at Gadlys (Pershore 13.4C Cardiff 13.3C, Fyvie Castle 1.7C, Kinlochewe 10.8 mm Capel Curig 2.4 mm, Aberdaron 9.8h Valley 9.5h) [Max 10.3C Min 5.1C Pptn nil]. The 26th was another fine and sunny day making up for the terrible weather we have been having of late. Pressure 1037 mb was rising in the high centred over the SW Approaches. Low pressure now well N 964 mb SE Greenland and 988 mb North Cape. A little cloud over the mountaintops did start increasing for a while, then diminished, the afternoon mostly sunny (Fyvie Castle 14.4C Cardiff 13.0C, Benson -4.7C Swyddffynnon -2.6C, Lerwick 1.8 mm, Weybourne 9.9h Valley 9.7h) [Max 10.8C Min 3.4C Grass -2.2C Pptn trace dew]. Overnight with clear sky the 'snow moon' was very bright casting a white light on the ground. A cloudier morning on the 27th after a heavy dew and ground frost -1.2C on the grass, but no white frost was seen. Pressure was on 1042 mb over the UK and there was a light S'ly breeze. It was warm enough on the rockery bank with flowering heathers for bees to appear with their familiar humming, a sign of better weather to come. There are white, pink and red flowers in various places in the garden, they find the sunniest patch to feed not minding the colour it seems. Did some work in the sheltered 'hidden garden' today where it was quite warm. The first blue flowers of Chinodoxa 'glory-of-the-snow' are appearing, but sadly there is no snow left on the Snowdonia Mountains that I can see from my lockdown position () [Max 10.6C Min 3.8C Grass -1.2C Pptn trace dew]. The 28th of the month and the last day of climatological winter began calm and without a cloud in the sky. There had been a heavy dew and this had frozen into white frost on the grassy fields around the weather station. Visibility was good, but hazy with Saharan dust in the atmosphere, but none was detected deposited at ground level. Small tortoiseshell butterfly on primula in the garden on last day of winter.Many honey bees were on the heathers flowering on the rockery banks by 0930 GMT, one or two large wild queen bees were also seen. We have a large charm of goldfinches in the garden, more than 10, the BTO says that they are the eighth most common bird recorded in Garden Birdwatch garden list, having increased and moved north in recent years. They keep to lowlands and are not found in mountainous areas. When we first had a garden on Anglesey in the 1960's we were lucky to see one of the first nuthatches, the species northern limit at that time. They too have spread much further north in the last 60 years, they are in this garden too. Spotted the first butterfly of the season in the afternoon, a small tortoiseshell on flowering primroses and other primulas, not seen on the heathers. Insignificant rain UK everywhere (Chivenor 14.0C Trawsgoed 13.6C, Kinbrace -5.8C Capel Curig -3.6C, Tiree 0.4 mm, Aberdaron 10.2h Valley 10.1h) [Max 11.6C Min 2.1C Grass -2.8C Pptn nil].

The month ended with a total of 146.6 mm of rainfall (143%) & [162%] of averages largest since 2019, the 8th wettest in Llansadwrn since 1928. Although wintry at times the mean temperature 6.1C was (+0.2) & [+0.5] of averages, was lowest since 2018 and ranked 16th highest in station records since 1979. It was a sunny month, sunshine recorded at RAF Valley was 92.8h (114%) & [118%] of averages, 20th highest in February on the Anglesey record since 1931, there were 7 sunless days.

Winter was the second wettest on record with 510.6 mm (139%) & [156%] of averages. The mean temperature 5.4C was (-0.7) & [-0.2] of averages, lowest since 2018.



Home page Site map Top Home page Site map Top

March 2021

Wales was under COVID-19 tier four Lockdown...

March 1 - a very fine morning without a cloud in the sky, visibility at height was very good, but there was some layered inversion smoke haze along the Menai Straits. Pressure was steady on 1033 mb with out high 1037 mb drifted eastward to be over the North Sea at 0900 GMT, but still covering North Wales. A low 986 mb was over the Atlantic W of Shannon and mist and fog was prevalent in much of central and SE England. No so here, it was sunny all day and we had one of those marvellous aprés sunset skies we get here, peach and azure blue above lasting for about an hour (Porthmadog 14.9C, Shap -4.9C Bala -3.0C, Lerwick 0.8 mm, Aberdaron 10.5h Valley 10.3h) [Max 11.6C Min 3.1C Grass -2.1C Pptn trace dew]. Just a little cloud low in the sky to the E on the 2nd at 0900 GMT. There was a white frost on the grass early with the grass minimum recording -4.3C. A light E'ly breeze, very fine and sunny with bees out on the flowering heathers on the rockery banks. There was no colour in the sky after sunset tonight it looked very grey (Capel Curig 13.3C, Altnaharra -6.6C Capel Curig -4.8C, Scilly 1.4 mm, Morecambe 10.0h Valley 9.5h) [Max 11.6C Min 0.7C Grass -4.3C Pptn nil]. The 3rd seemed a raw damp day when I went out for the obs, very grey with very poor visibility in low cloud. The breeze was NE'ly and I suspect the air was coming off the North Sea so we could call it the haar. The term is used in eastern Scotland and north-east England, its origin is related to Middle Dutch haren. The temperature was 4.3C and the sun was looming through at times was looking white. Pressure was steady on 1028 mb so it was anticyclonic gloom, the jetstream was far north, in fact north of Greenland, Iceland and just on Cap Nord. There was a trough of low pressure 1023 mb over the South West Approaches and most of the UK and Ireland had mist and fog (Camborne 13.5C Bala 10.3C, Dalwhinnie 0.6C, Braemar -7.6C Bala -2.3C, Milford Haven 13.2 mm, Shap 7.6h Aberdaron 2.7h Valley 0.4h) [Max 5.7C Min 1.4C Grass -2.8C Pptn nil]. Another poor day on the 4th and a bit colder 3.7C at 0900 GMT. Little change in pressure with high 1038 mb SE Iceland stretching to the UK. There was a cold front NE Scotland heading southwards. The sun did break through briefly about noon. There was a little rain when the weak cold front passed over between 19 and 20 GMT (Myerscough 10.9C Pembrey Sands 8.3C, Dalwhinnie 2.2C, Shap -2.6C, Bedford 15.4 mm. Tiree 5.8h Valley 0.3h) [Max 5.6C Min 3.1C Rain 0.4 mm]. A much better day on the 5th after a frosty night beginning fine and bright with a few cumulus clouds, but still on the cool side with 3.8C at 0900 GMT. A mostly sunny day the temperature rising to 7.0C just after noon. High 1036 mb was over Scotland and rising here 1034 mb. North Wales had the best of the weather today with the slow moving cold front over the Severn estuary (Porthmadog 8.7C, Lake Vyrnwy 2.9C, Loch Glascarnoch -7.1C Whitechurch -1.7C, Lerwick 2.0 mm, Valley 8.0h) [Max 7.0C Min 1.3C Grass -4.1C Rain nil].

The 6th began brightly after a 'dry frost' well I didn't see any white early on although at 0900 GMT the grass was slightly wet so it could have melted. Measured dew deposition was 0.13 mm and the AWS gauge had tipped recording 0.2 mm. The air temperature had been -0.6C with -6.4C on the grass overnight, there was ice on water too. The temperature now 2.6C rose to 7.3C at 1213 GMT the relative humidity 54% in cold dry air. Pressure was steady on 1037 mb in our own North Wales high. The sky was half cloudy with altocumulus and cumulus clouds and the day fair with sunshine at times, most other places except Cornwall were cloudier today (Gosport 9.4C Trawsgoed 8.5C, Braemar -8.5C Capel Curig -5.8C, Stornoway 5.2 mm, Bude 9.2h Valley 7.9h) [Max 7.3C Min -0.6C Grass -6.4C Pptn nil]. A fine, but dull morning on the 7th feeling cold with a temperature of 3.4C after light air and ground frosts overnight. Dew/ frost deposition was 0.04 mm. Visibility was moderate to good and it was quiet with persistent wood pigeon cooing in the trees. Pressure was still high 1030 over Wales at midnight, the centre had moved to near Gloucester. There was a detached occlusion over Ireland and this was given us the cloudy morning. By 1030 GMT the sky had brightened with sunny spells developing into the afternoon with a maximum temperature of 8.7C at 1539 GMT. Wind strengthened during the evening (Killowen 12.7C Llansadwrn/ Aberdaron 8.7C, Sennybridge -7.7C, Wick 19.0 mm, Camborne 8.1h Valley 5.3h) [Max 8.7C Min -1.0C Grass -6.3C Pptn trace]. Not quite as cold overnight on the 8th being windy and overcast with a little rain around 01 GMT, but a ground frost of -4.2C was recorded by the morning, precipitation on the grass was 0.06 mm with a trace in the rain gauge. Some weak sunshine at 0900 GMT the sky clearing a little. The afternoon was sunny for a while. Traffic on Welsh roads had been 60% higher during the current lockdown. Certainly the traffic past the weather station in afternoon has been more than usual, between 60 and 80 vehicles an hour, up to 100 at times, normally its around 20 to 25 an hour. It is a mystery in the lockdown with only essential journeys allowed and travel for for recreation or taking exercise not allowed, where they have been going. I have not been able to visit any botanical monitoring sites (Murlough 13.2C Usk 12.2C, Lerwick 4.8C Capel Curig 7.1C, Okehampton -5.5C Bala -3.3C, Dunstaffnage 13.6 mm Porthmadog 0.2 mm, Camborne 8.4h Aberporth 7.7h Aberdaron 2.3h) [Max 8.6C Min 1.9C Grass -4.2C Pptn 1.4 mm]. Pressure on the 9th 1019 mb was falling and the dull weather continued with thicker low stratocumulus clouds. The jetstream was strengthening and there was low 994 mb W of Ireland. Our local high pressure system had disappeared, Azores high 1030 mb had a ridge to Brittany and it was sunny in SE England. After a glimpse of bright sunshine around 0830 GMT the cloud had thickened and the rest of the day was sunless. Light to moderate rain with temperature rising from 6.5C in the late evening with the wind strengthening to gale force by midnight (St James Park 14.4C Usk 12.1C, Benson -4.6C Usk -4.4C, Tyndrum 20.6 mm Capel Curig 4.0 mm, East Malling 10.2h St Athan 3.2h) [Max 8.8C Min 5.4C Grass 1.4C Rain 30.0 mm]. On the 10th it was a very wet morning after a rough night, Capel Curig recorded a gust of 86 mph, Aberdaron 84 mph, Valley 58 mph. The jetstream was set up over the UK and there was a low 9599 mb between Iceland and Scotland with another in the wings 968 mb W of Ireland. Heavy rainfall in Wales 48 h up to 06 GMT on the 11 Mar 2021.Pressure here 1005 mb was falling. At 0900 GMT 30.0 mm of rain was measured, there were several large pools of water on the Gadlys 'old cricket field' and water was standing at the weather station. The temperature was 8.8C (RH 98%) and rising, continuous light to moderate rain turned heavy just before noon and very heavy at 1443 GMT was falling up to 16 mm/h, the pools of water on the 'old cricket field' had coalesced into larger pools. Rainfall over 48h to 06 GMT on he 11th at Capel Curig totalled 89 mm, here 53.8 mm and Gorwel Heights 26.2 mm. The maximum temperature 10.6C was at 1830 GMT before a cold front and deepening wave trough crossed here, associated with low 961 mb off W Scotland at 1800 GMT. The roof top anemometer recorded 48 mph when a slate was removed from the roof. Wind run (00-00 GMT) was 410 miles (Hawarden 13.7C, Dalwhinnie 6.0C Tredegar 9.6C, Dalwhinnie 0.4C Tredegar 3.8C, Capel Curig 80.2 mm, Kinloss 4.6h Valley nil ) [Max 10.6C Min 6.5C Rain 23.8 mm].

After the rain and wind storms of the past 48h the 11th dawned fair. The sky was overcast with layered stratiform clouds, but in thinner patches the sun was just visible. Visibility was good albeit hazy. Pressure 990 mb was rising quickly. Deep marine convective clouds were impacted north-west Wales and Scotland during the day. It was still breezy at times, but moderated during the afternoon when between showers of rain, ice pellets and sleet (heaviest 1440 GMT) it was sunny. Fixed a new slate on the roof during one of the better spells. Wind run today was 340 miles (Writtle 13.2C Usk 10.7C, Dalwhinnie 2.1C Lake Vyrnwy 4.6C, Lake Vyrnwy 32.6 mm, Shoeburyness 6.3h Aberdaron 5.2h) [Max 9.0C Min 6.1C Pptn 2.7 mm].MetO analysis chart at 0000 GMT on the 13 Mar 2021. The 12th was a rather dull and cold day, still breezy and the soil was wet and muddy. Pressure 998 mb was still rising with low 960 mb S Norwegian Sea. High 1031 mb was over the Azores and there were shower troughs over the UK. A frontal-wave depression developed W of Shannon at noon and tracked over Shannon by 1800 GMT and proceeded across Anglesey (983 mb at 2300 GMT) reaching Liverpool at midnight. Managed to fit in a lockdown stay-at-home 1 miler round the wood and garden in the afternoon, too cold and muddy to do work in the garden (Teddington 11.7C Usk 10.4C,Dalwhinnie 0.1C Tredegar 1.0C, Lake Vyrnwy 29.4 mm, Kinloss 8.5h Hawarden 4.8h) [Max 8.0C Min 4.0C Pptn 3.4 mm]. It was overcast at first on he 13th the 5.1C at 0900 GMT feeling chilly in the WSW'ly breeze. Pressure 993 mb was rising here, the jetstream was located over the English Channel with low 962 mb S Norwegian Sea and 962 mb 977 mb North Sea. This had an associated cold front over France. It was a blowing a bit in the Channel with gusts of 54 mph recorded at Calais. We were in a flow of Polar open celled convective cloud, there were snow showers over the mountaintops of Snowdonia. The sky started to clear by 10 GMT and the afternoon had some sunny spells. Sycamore leaves on saplings and snowberry in the wood were opening. Gooseberry was also starting to leaf and the sticky buds on horsechestnut looked fit to burst (St James Park 11.3C Cardiff 10.1C, Aboyne -4.1C, Blencathra 28.8 mm Lake Vyrnwy 26.4C. Tiree 8.4h Hawarden 6.4h Valley 4.0h) [Max 7.7C Min 4.4C Pptn 0.4 mm]. A dull day on the 14th, a little rain overnight left concrete and grass wet at 0900 GMT. Visibility was moderate, but the mountaintops were obscured. Pressure 1017 mb was rising with Atlantic-high 1030 mb off Iberia and low 982 mb S Norwegian Sea. Showery rain around noon then wit strengthening wind turning wet with heavy rain just before 18 GMT accumulating 17.2 mm. Rain ceased before midnight (Cardiff 12.5C, Aboyne 0.4C, Capel Curig 27.0 mm, Weybourne 7.5h St Athan 3.8h Valley nil ) [Max 8.4C Min 4.5C Pptn 17.2 mm]. A fine morning in the 15th, though damp underfoot, it was brightening by the minute. Fast trainer jets from RAF Valley were in the vicinity, flying continued on and off through the day. We had two small Texan trainers as well later. A warm feeling day, the temperature rising to 13.3C, I had to take my pullover off working in the garden in the sunny afternoon (Derrylin Cornahoule 14.8C Mumbles Head 13.8C, Drumnadrochit -0.1C, Winchcombe Sudeley Castle 12.6 mm Swyddffynon 5.6 mm, Weybourne 9.6h Bala 6.2h Valley 5.5h) [Max 13.3C Min 5.3C Pptn 3.2 mm].

The first 15-days had temperatures a little below normal the mean temperature 5.9C (-0.9) & [-1.1] of averages. Precipitation totalled 82.5 mm (100%) & [105%] of averages with 53.8 mm falling on the 9th and 10th.

A dull morning under low cloud with mist and rain early on the 16th, but by 0900 GMT there was some improvement, the rain had stopped and visibility was good. Pressure 1029 mb was rising with high 1035 mb Biscay to W of Ireland. Low 1006 mb E Iceland had associated frontal cloud over the Irish Sea. By 10 GMT the cloud was lifting and breaking up. The afternoon was sunny (Pershore 17.9C Cardiff 17.4C, Baltasound -2.8C, Loch Glascarnoch 14.6 mm Gogerddan 8.8 mm, Tiree 10.2h Lake Vyrnwy 6.5h) [Max 13.6C Min 8.0C Pptn nil]. Another cloudy morning on the 17th, but it was bright and fair with very good visibility. Weak sunshine then a sunnier afternoon (Milford Haven 15.4C, Katesbridge -2.3C Trawsgoed -1.7C, Lerwick 2.8 mm, Camborne 7.9h Aberdaron 6.2h) [Max 13.3C Min 3.0C Pptn 0.3 mm]. Jetstream 300 mb GFS analysis for 00 GMT on 19 Mar 2021. Courtesey of SFSU Meteorology. Fog developed after midnight on the 18th and in the morning with little or no wind visibility was very poor with a fine drizzle. Pressure 1034 mb was high with Omega block high 1040 mb W of Shannon, but not doing us any good with cloud trapped within it thick enough for more drizzle at times through the day (Edinburgh Botanic Gardens 19.0C Usk 16.1C, Yeovilton -2.4C Swyddffynnon -1.6C, Weybourne 4.4 mm, Kinloss 9.9h Bala 4.7h) [Max 10.4C Min 4.5C Pptn 0.6 mm]. Fog at times overnight and on the morning of the 19th it was still misty with good visibility. Pressure was still high 1031 mb the high 1038 mb W of Ireland was edging westwards with the jetstream over the North Sea as far as N Spain. I have used SFSU Meteorology for jetstream charts for 20 years, unfortunately the California Regional Weather Server is no longer being maintained as Prof. David Dempsey passed away last year. It had website functioned automatically till now. A cold front was over East Anglia associated with low 974 mb Svarlbard. Fine, but dull in the afternoon (Tyndrum 17.4C Porthmadog 14.8C, Braemar -2.2C Porthmadog 2.7C, Wainfleet 2.8 mm, Shoeburyness 11.1h Aberporth 2.6) [Max 10.8V Min 6.4C Pptn nil]. Much the same on the 20th with low cloud and mist hanging over the island with moderate visibility. Pressure remaining high was steady on 1034 mb with high 1037 mb W of Shannon. A remnant frontal system over southern Britain kept the S dull and misty while the N was bright with some sunshine. Fine drizzle and spots of rain from 1700 GMT of no measurable volume. Sunless day (Aboyne 17.6C Scolton 12.6C, Aboyne -3.3C, Baltasound 4.0 mm, Charterhall 10.5 Bala 0.9h) [Max 10.3C Min 7.3 Pptn trace]. The 21st began a little brighter with a glimpse of sunshine before 0900 GMT. There had been heavy dew overnight with the grass minimum down to 0.5C. Pressure was on 1032 mb with the high moved to be over the Celtic Sea. There was a remnant weak cold front over Wales, there was a short spell of drizzle at 1330 GMT (unmeasureable amount) and the sun appeared again under the cloud sheet at sunset (Usk 14.2C, Braemar -3.9C Anglesey Mona 4.2C, Lerwick 1.2 mm, Glasgow 11.1h Lake Vyrnwy 9.2h) [Max 9.1C Min 5.4C Grass 0.5C Pptn trace]. After a cool night the morning of the 22nd was fine, but dull. High 1029 mb was stationed over the Celtic Sea and was a little lower 1027 mb here. Visibility was good, no snow was seen on the mountains. The day was sunless, but dry albeit the air seemed a little damp at times in the afternoon (St James Park 15.0C Tredegar 12.3C, Aboyne -5.1C Sennybridge -4.2C, Lerwick 2.0 mm, St Athan 10.8h) [Max 9.6C Min 2.8C Pptn nil]. Much the same on the 23rd except the high pressure had begun to decline and now centred 1029 mb SE Europe. Here pressure 1020 mb was falling slowly with a frontal wave low 988 mb off the Western Isles of Scotland having an associated cold front W of Ireland. Dates of flowering of blackthorn in Llansadwrn 1996-2021. It was dull with a cold breeze the SSW'ly picking up. Slight showers of rain in the afternoon with rain coming along later in the evening on the cold front. Blackthorn is now flowering in the hedgerows around Llansadwrn including along the A5025 to Pentraeth and in Beaumaris, unlike hawthorn the conspicuous white flowers appear before the leaves unfold. Flowering 19 days later than last year, but just a day later than the median date over the past 26 years (Hereford 14.0C Cardiff 13.8C, Santon Downham -3.2C, Achnagart 6.6 mm Capel Curig 0.8 mm, Camborne 7.9h St Athan 1.4h) [Max 9.2C Min 6.9C Pptn 3.2 mm]. As the sky cleared after midnight on the 24th it turned a little colder with a touch of ground frost. A fine and breezy morning with a few cirrus and cumulus clouds and good visibility. The day was mostly sunny and the brightest of the month and year so far with solar radiation of 15.14 MJ m -2 and brightest 758 W m -2 at 1135 GMT; Valley 9.6h sunshine. The highest temperature 11.7C was at 1408 GMT (Usk 15.1C, Kinbrace -1.0C Anglesey Mona 3.0C, Dunstaffnage 19.0 mm Capel Curig 11.4 mm, Valley 9.6h) [Max 11.7C Min 4.8C Pptn 0.6 mm].

Flooded dune slacks at Aberffraw dunes.

A mostly cloudy morning on the 25th after showers of rain overnight, cumulus and lenticular altocumulus clouds. Pressure was steady on 1016 mb with low 979 mb SW Iceland and high 1027 mb over the Pyrenees. The breeze was cold at 0900 GMT, visibility was moderate and there was a little sunshine later. Light showers end of the afternoon (Hull 15.3C Hawarden 14.7C, Bournemouth -1.8C, Capel Curig 20.0 mm, Manston 9.0h Bala 5.6h) [Max 11.1C Min 6.6C Pptn 17.8 mm]. Heavy showery rain after midnight on the 26th with bursts up to 48 mm/h at 05 GMT including wet graupel and 58 mm/h at 0626 GMT that including sleet later about 0830 GMT. Total precipitation recorded at 0900 GMT was 17.8 mm the third largest daily fall of the month. Pressure 1004 mb was rising from 1000 mb at 0616 GMT. A cold front associated with low 973 mb SE Iceland lay across Cape Wrath, Anglesey, Pembrokeshire Islands, Cornwall and Scilly Isles. Scattered clouds with good visibility, snow was seen lying at 2500 ft on the Carneddau Mountains, further wintry showers later in the afternoon (Cavendish 13.9C Usk 11.4C, Lough Fea 0.9C, Achnagart 35.6 mm Sennybridge 14.2 mm, Aberdaron 7.8h Valley 5.7h) [Max 9.4C Min 4.3C Pptn 0.6 mm]. Wintry after midnight on the 27th with some ice precipitation recorded on the hail pad. It was a fine morning with 5 oktas mixed cloud cover and sunny. The strengthening SW'ly wind felt cold the temperature 6.4C. Some further weak sunshine in the afternoon the temperature rising to 10.4C. Warmer in the greenhouse where the Black Hamburg grape had begun to shoot () [Max 10.4C Min 2.3C Pptn 5.8 mm]. It was wet and windy on the 28th, very poor misty visibility at 0900 GMT with moderate rain. There was standing water at the weather station and pools of water had formed again on the old cricket field. There was a cold front over the North channel with low 954 mb SE Greenland. Here pressure 1014 mb was rising after bottoming at 1011 mb at 0326 GMT. A dark sunless day with maximum light level of only 114 W at 1130 GMT. Wind run totalled 450 miles here gusting to 43 mph today compared with 275 miles at Gorwel Heights gusting to 50 mph. Heavy rain up to 20 mm/h fell at 1733 GMT (Normanby Hall 16.2C Hawarden 14.6C, Dalwhinnie 2.3C, Shap 109.4 mm Capel Curig 103.6 mm, Lerwick 6.2h Valley nil) [Max 10.9C Min 6.4C Pptn 13.0 mm]. Another overcast and dull day on the 29th with slight rain and drizzle at 0900 GMT. Visibility was very poor and it was a mild 10.8C with 95% relative humidity. The overnight minimum air temperature was 9.7C the highest of the month. The light level was only 63 W, but it did rise to 132 W in he afternoon. The temperature in Llanfairfechan about 1335 GMT at Gorddinog AWS rose to 15.3C and 15.1C at Gorwel Heights, here it got no higher than the earlier 10.8C (Writtle 20.4C Hawarden 16.0C, Okehampton 6.4C, Achnagart 81.6 mm Capel Curig 21.4 mm, Manston 11.9h Hawarden 10.8h Valley nil) [Max 10.8C Min 9.7C Pptn 0.3 mm]. Dates of arrival of the chiffchaff in the garden in Llansadwrn 1998-2021. A quite different day on the 30th beginning almost calm and hardly a cloud in the rather milky looking sky the result of a lot of Saharan dust in the air, but none had been deposited. I was greeted by the first chiffchaff of the season to reach here. Five days later than last year and the median date of arrival on 22-y records, rank 7th latest. Pressure 1028 mb was rising with high 1033 mb S Iceland. Trainer jets from Valley were in the vicinity. Sunny and warm in the afternoon the temperature rising to 18.6C, highest of the month, beating the 17.7C recorded at Gorwel Heights (Kew Gardens 24.5C Gogerddan 21.6C Gadlys Gardens 18.6C, Santon Downham -1.7C, Achnagart 73.4 mm Usk 0.6 mm, Shoeburyness 12.1h Hawarden 9.5h Valley 9.1h ) [Max 18.6C Min 6.2C Pptn nil]. Another fine sunny day on the 31st, a little more cloud in the morning, still the milky sky with hazy sunshine. There was a deposit of yellow/ green pollen from some of the trees with a trace of a darker colour possibly Saharan dust. There was fog on the Irish Sea this affecting coastal areas including Rhosneigr and RAF Valley. Valley was on RED at 10 GMT and there was no flying today. The first bluebells of the season were out in the wood, six days earlier than last year and the median date. The temperature reached 16.8C just after 1300 GMT and solar light of 679 W (Weybourne 23.9C Bala 21.1C, Eskdalemuir -0.2C, Lentran 26.6 mm, Hawarden 9.6h Valley 7.6h) [Max 16.8C Min 9.2C Pptn nil].

Another wet month having a total of 124.7 mm of rainfall (151%) & [159%] of averages largest since 2019, the 11th wettest March in Llansadwrn since 1928. Occasionally wintry at times the mean temperature 7.4C was (+0.5) & [+0.4] of averages, was highest since 2019 and ranked 15th in station records since 1979.



Home page Site map Top Home page Site map Top


April 2021

April 1 - began brightly and very fine with a light and cool ENE'ly breeze. The sky was very milky again and visibility moderate the result of a lot of Saharan dust in the atmosphere mentioned several times by BBC weather forecasters. Cloud was difficult to see. a mixture of cirrus and cumulus. Little dust was deposited here, my daily sample contained just a trace of dust, it was mostly pollen. Pressure 1025 mb was rising with high 1036 mb S Iceland with a remnant cold front lying across N Wales from N Ireland to The Wash. Sunny afternoon (Bude 17.8C Pembrey Sands 17.3C, Loch Glascarnoch -3.0C Bala 4.9C, Dunkeswell 1.4 mm, Loch Glascarnoch 12.2h Valley 8.8h) [Max 12.1C Min 7.5C Pptn nil]. A very fine and sunny morning on the 2nd, but there was a cold felling ENE'ly breeze. Pressure was high 1032 mb and rising within high 1040 mb S Iceland with a ridge extending as far as the southern North Sea and Thanet. With some of the native trees starting to flower the slightly dusty surface samples included yellow/ green pollen. A sunny day though on the cool side, it was nice in sheltered spots out the wind (Derrylin Cornahoule 15.9C Porthmadog 14.8C, Tulloch Bridge -6.1C Hawarden -0.6C, Nosig rain, Thomastown 12.5h Valley 12.2h) [Max 9.7C Min 3.0C Grass -0.6C Pptn nil]. Much the same on the 3rd with good slightly hazy visibility. A slight ground frost -1.8C, but you had to be up early to catch sight of the white frost on grass. Pressure was steady on 1030 mb with high-pressure 1040 mb lying to the north-west encompassing the British Isles. The weather best in the west today. Did some grass management today, the mowers took a bit if starting after winter inactivity. After a sunny afternoon the sky at sunset was an unusual colour perhaps affected by the heavy Saharan dust in the atmosphere The moon was also coloured slightly orangy (Drumnadrochit 17.6C Porthmadog 14.7C, Tulloch Bridge -5.8C Bala -2.4C, No significant rain, Glasgow 12.5h Valley/ Aberdaron 12.3h) [Max 10.7C Min 3,3C Grass -1.8C Pptn nil]. A very fine and sunny morning on the 4th after a touch of ground frost, the breeze felt cold. There were coastal fog patches off the sea early in the day. Pressure was on 1029 mb the high now 1037 mb S Greenland and W of Ireland with ridge to SE England. Low 965 mb Svarlbard and a cold front between Iceland and Scotland was expected to sweep southwards later. Observing the sky at 0900 GMT a small cumulus cloud passed before the sun, nothing else. There was some early sea fog around around north-western coast, but it soon burned off to give another fine sunny and slightly warmer day on the island of Anglesey. Pressure was on 1029 mb the high now 1037 mb S Greenland and W of Ireland with ridge to SE England. Low 965 mb Svarlbard and a cold front between Iceland and Scotland was expected to sweep southwards later (Pershore 17.9C Usk 17.2C, Benson -5.2C Sennybridge -3.7C, Cassley 14.0 mm, Shobdon 12.2h Hawarden 11.9h Valley 11.3h) [Max 13.4C Min 1.1C Grass -2.3C Pptn 0.4 mm]. Dwarf white Rhododendron has been flowering in the garden since January.Overnight on the cold front there was a dusting of snow on the Snowdonia Mountains on the morning of the 5th including at Ogwen at 1000 ft. At 0900 GMT pressure 1023 mb was rising and the temperature 4.4C, but it was mostly sunny with a few cumulus clouds in the vicinity. Low 9667 was over the Gulf of Bothnia and there was a cold front over N Wales and S England with the windflow directly from E Svarlbard. Visibility was very good, almost clear in the clean Arctic air. At 1620 GMT we had a shower of snow pellets, this was followed at 1625 by small snow flakes, cold and wintry in the north. Today's maximum temperature was 7.7C, joint coldest day of the month. At Svarlbard today Max -6.8C Min -8.5C Snow 59 cm; Ny Alesund Max -6.8 Min -10.2C Snow 59 cm; Tromso Max 2.8C Min -4.5C Snow 15 - 80 cm (Bournemouth 10.6C Cardiff 9.7C; Aviemore -5.4C, Kinlochewe 8.4 mm Capel Curig 2.2 mm; Glasgow 12.5h Valley 10.1h) [Max 7.7C Min 2.8C Pptn 1.0 mm].

Winter was not over yet on the 6th with snow falling to low levels in the morning. Snow was lying at 1000 ft at Ogwen and we had a squally shower of snow pellets at 0907 GMT followed by snow at 0915 GMT briefly covering cold surfaces of car and workshop roof. Visibility in the precipitation reduced to very poor, but it soon improved and the day had some sunny spells. Pressure was 1024 mb with convergent cloud formation over the Irish Sea south from the North Channel. Today's maximum temperature joint lowest of the month (Pershore 9.8C Cardiff 9.7C, Eskdalemuir -4.2C Libanus -3.6C, Kinlochewe 12.0 mm Capel Curig 10.0 mm, Prestwick 10.7h Hawarden 8.7h Valley 5.4h) [Max 7.7C Min 0.1C Grass -2.3C Pptn 3.0 mm]. The wintry spell continued on the 7th with showers of ice precipitation including snow pellets, slight snow and at times sleet. The temperature at 0900 GMT was 3.2C, lowest of the month so far. A cold front over the Irish Sea was associated with low 1012 mb Iceland with pressure here 1025 mb between high 1032 mb off SW Ireland and low 972 mb North Cape. Bright with glimpses of sunshine (Holbeach 14.2C Cardiff 12.9C, Fyvie Castle -2.4C, Achnagart 46.8 mm Scolton 2.8 mm, East Malling 7.4h Aberporth 6.6h Valley 0.3h) [Max 7.9C Min 0.7C Grass -1.8C Pptn 1.5 mm]. Snake's head fritillaries in our meadow looking at their best today.Seagulls from far and wide arrive for ploughing at Gadlys Old Cricket Field.On the 8th pressure 1020 mb was falling with deepening low 986 mb between Iceland and Scotland. A warm front was along the spine of the UK with high pressure 1029 mb over Austria. A cold front began moving over NW Scotland at noon. Windy at times gusting 36 mph in the afternoon with glimpses of sunshine (Holbeach 14.2C Cardiff 12.9C, Fyvie Castle -2.4C, Achnagart 46.8 mm Scolton 2.8 mm, East Malling 7.4h Aberporth 6.6h Valley 1.4h) [Max 10.1C Min 3.1C Grass 1.4C Pptn 0.5 mm]. A cold front had passed over at 0030 GMT with temperature drop and wind veering around the compass with precipitation at 0059 GMT. At 06 GMT the cold front had reached S Wales. The morning of the 9th was rather again at 0900 GMT 5.8C with slight showers of ice precipitation. A shower of ice precipitation at 0925 GMT. Bright later with sunshine in the afternoon. A blackcap was singing today. Ploughing (below) attracted many seagulls to the old cricket field during ploughing today. The shelter belt trees beech and sycamore are just beginning to burst their buds (Writtle 14.7C St Athan 11.4C, Kinbrace -3.7C, Kinlochewe 8.0 mm Mumbles head 6.4 mm, Glasgow 13.0h Valley 7.1h) [Max 9.6C Min 4.1C Pptn 0.1 mm].

Ploughing at Gadlys.

On the 10th we were in a cold plunge from from the Arctic with a sprinkling of snow on the Snowdonia Mountains and snow reported at Manchester Airport and Wilmslow, Cheshire The Jet Stream was strong over Africa, pressure was on 1017 mb with highs 1016 mb S North Sea and Atlantic 1033 mb W of Ireland. The temperature here at 0900 GMT 5.3C and dry and sunny with mountain cumulus and fair weather cumulus overhead, warmer in the S with rain to the SE (Plymouth 13.6C Cardiff 11.9C, Shap -7.8C Trawsgoed -5.1C, Almondsbury 7.4 mm Libanus 3.2 mm, Aberdaron 12.9h Valley 12.0h) [Max 8.4C Min 0.5C Grass -3.7C Pptn nil]. Sferics at 0933z on 11 April 2021. Courtesy of blitzortung.org/.A band of thundery showers passed over N Wales on the morning of the 11th, thunder was heard at 0850 GMT. Still in the cold airflow from the N there was snow on the mountains above 2750 ft. There had been a touch of air frost -0.1 C and on the grass it had been down to -4.3C, both lows of the month. Backlit cumuli were pretty impressive at 0900 GMT with a cumulonimbus clouds in the vicinity to the N and S of the station. Fine and sunny at times. It was 4.8C with a cold feeling N'ly wind, this rising to 8.8C at 1452 GMT following a reflective 915 W m -2 during frequent sunny spells in the afternoon. There was a moderate spell of sleet just before midnight (Plymouth 11.2C Usk 10.4C, Tulloch Bridge -8.7C Sennybridge -6.3C, Rochdale 6.0 mm Valley 3.2 mm, Prestwick 12.1h Hawarden 11.2h Valley 7.0h) [Max 8.8C Min -0.1C Grass -4.3 C Pptn 3.0 mm]. Sleet continued after midnight on the 12th for a while turning to showers of very small snow pellets (graupel) in the small hours with sleet at 0740 GMT.; At 0900 GMT visibility was very good in clean northern air, snow was lying at 1000 ft at Ogwen early and was lying at at 1500 ft generally at 0900 GMT and as low as 600 ft in places on the northern slopes of the Carneddau. It was sunny at times, but feeling cold in the wind, the maximum 8.4C at 1540 GMT (Plymouth 12.5C Pembrey Sands 11.4C, Tulloch Bridge -9.4C Sennybridge -2.9C, Castlederg 12.6 mm Valley 6.0 mm, Stornoway 13.1h Hawarden 11.5H Valley 5.2h) [Max 8.4C Min 0.6C Grass -1.8C Pptn nil]. On the morning of the 13th there was snow lying at 2500 ft on the Snowdonia Mountains, but in the garden here the flowers on our damson tree were beginning to open. So we don't want an air frost, overnight although the grass minimum recorded -2.3C in the air the minimum was 2.4C. Pressure was on 1033 mb with high 1034 mb Belgium. There was a warm front over the Western Isles associated with frontal wave S of Iceland. Pressure was low 1011 mb Adriatic and the Med. The morning was mostly cloudy, but it cleared up later in the afternoon and evening (Astwood Bank 14.6C Usk 13.1C, Braemar -8.0C Sennybridge -4.2C, Salsburgh 11.2 mm Sennybridge 3.6 mm, Kinloss 13.3h Aberdaron 11.3h Valley 5.2h) [Max 11.2C Min 2.4C Grass -2.3C Pptn 0.5 mm]. Harrowing at Gadlys, Llansadwrn, Ynys MonHardly a cloud in the sky on the morning of the 14th with slightly hazy very good visibility. There was a fresh sprinkling of snow on the mountaintops. There has been some sea fog early on the west coast with Valley on RED 0550 & 0650z. Very fine and sunny. Spotted a holly blue butterfly in the garden in the afternoon, the 'old cricket field' to the SW of the weather station was disk harrowed today (Castlederg 15.3C Porthmadog 14.9C, Braemar -6.0C Sennybridge -3.2C, Cardinham 1.6 mm, Aberdaron 13.2h Valley 11.2h) [Max 12.6C Min 2.3C Grass -2.3C Pptn nil]. Another fine day day on the 15th and starting off calm here had been a ground frost with white frost seen at 08 GMT. The generally blue sky looked slightly milky at low levels and there was a little mist in the Menai Strait. Sunny day (Glasgow 15.9C Trawsgoed 13.5C, Aboyne -6.3C Sennybridge -4.1C, Cromer 1.8 mm, Kinloss 13.6h Aberdaron 13.2h Valley 10.9h) [Max 12.8C Min 2.4C Grass -2.4C Pptn nil].

The first 15-days temperatures were well below the monthly average the mean temperature 6.2C (-3.1) & [-2.9]. Equal second lowest with 2013 since 5.9C in first 15-d of 2000 in 43-y station records, since 1979. It was also very dry, precipitation just 10.0 mm (19%) & [15%] of averages. Sunshine had averaged 4.0 h per day (68%) & [74%] of the months average total

Very fine and sunny on the 16th with some snow persisting on the mountain summits, very good visibility was slightly hazy. Around noon it was cloudier with classic convective cloud development over SE Anglesey, Llansadwrn and he Carneddau Mountains, due to convergent airflows SW=NE, this cleared away in the afternoon. The field adjacent to the weather station was drilled with seed today again attracting a mass of seagulls (Aboyne 14.9C Hawarden 13.7C, Aboyne -7.3C Sennybridge -5.1C, Wittering 1.6 mm Dundrennan 13.1h Aberdaron 12.3h Valley 11,8h) [Max 11.4C Min 2.4C Grass -3.2 mm Pptn nil]. Seed sowing at Gadlys, Llansadwrn.On the 17th in the morning visibility was good though moderately hazy. With the fine sunny weather and increased traffic following easing of lockdown regulations, there was an increase in airborne pollutants including ozone. At Marchlyn Mawr reservoir at 2100 ft an instrument recording ozone (Welsh Air Quality Forum) measured 109 µg per m-3 , the highest for a while. Rise in temperatures also thawed much of the remaining light snow on the mountaintops. Remnants with a 30% cover at 3050 ft were observed at 0900 GMT. Calm at first a light SW'ly breeze backing S'ly, very fine and sunny. A Coastguard helicopter flew over travelling from NE to SW. Pressure was on 1031 mb in a ridge from Scandinavian high 1038 mb centred over S Norway. Strangely, a misty drizzle developed briefly by 0915 GMT, then cleared away, precipitation of no measurable volume. By 11 GMT the breeze was N-NE'ly and picking up to force 2/3 by afternoon. It was very hazy in the afternoon and felt warm in the sun, cool in the shade with the breeze then off the sea. Holly blue and speckled wood butterflies were seen around the garden (Preston 15.5C Usk 14.9C, Sennybridge -5.6C, Wiggonholt 0.2 mm, Shobdon 13.1h Lake Vyrnwy 12.8h Valley 11.8h) [Max 14.1C Min 2.4C Grass -3.0C Pptn tr]. Local dust raised during unusually dry weather.There was an unpromising start to the 18th with overcast skies and thickening cloud. Visibility was good with moderate haze with the ozone level on moderate 4 with 104 µg per m-3 . There was rain to the NW of Anglesey and we had a milder airstream the cold plunge had moved a little eastward, but was reaching as far as the western Med. It was dry, however, and soon became fair with the cloud thinning and weak looming sunshine appearing. Pressure was on 1026 mb with high 1034 mb S Norway. A mass of frontal cloud associated with low 991 N Iceland lay on the W of Ireland. The afternoon was sunnier and warm (St James Park 16.0C Cardiff 15.6C, Woburn -4.2C Sennybridge -2.8C, Castlederg 8.8 mm, Waddington 12.9h St Athan 10.2h Valley 3.2h) [Max 13.1C Min 3.3C Pptn nil]. Very fine on the 19th although mostly cloudy to start with moderate hazy visibility. A 0900 GMT it was feeling warmer with a temperature of 13.1 C, the highest this year so far at this time. The afternoon was mostly sunny. The soil surface is very dry and cracked at present. The moisture content determined today had fallen under grass to 41.4%, below the saturated water percentage (SWP) 70% for the local soil, but to 17.7% on the bare Met plot near the permanent wilting percentage (PWP) 15.2%. The top 2 cm of grass contained 79% moisture, just above the SWP (Northolt 18.3C Hawarden 16.8C, South Newington -4.1C Sennybridge -2.2C, Stornoway 10.0 mm, Rostherne 13.1h Hawarden 12.7h Valley 9.7h) [Max 15.7C Min 4.3C Grass -0.4C Pptn nil].

A fine morning on the 20th with no overnight frosts. Visibility was moderate with thick haze and the sky looked very milky a combination of photochemical smog and a little dust. Although the temperature was 10.9C the NE'ly breeze felt chilly. Pressure was steady on 1019 mb with high 1025 mb to the north-west S of Iceland and W of Scotland. There was a cold front over the North Channel, it was cloudy with some rain in NW Scotland. Fair here, with mostly weak sunshine and not a drop of rain (Pershore 18.6C Usk 18.3C, Fair Isle 8.7C Aberporth 11.5C, Bournemouth -1.7C Sennybridge -0.5C, Aultbea 7.8 mm, Yeovilton 12.0h Hawarden 8.3C Valley 4.8h) [Max 12.9C Min 4.7C Grass 2.6C Pptn nil]. Sun pillar detail, courtesy Snowdonia Mountain Community & BBC.Just a few cumulus clouds on the 21st, but still very hazy with weak sunshine, visibility poor. Low cloud/ fog could be seen across Liverpool Bay. Clearer sunshine in the afternoon, dry (Bude 17.7C Cardiff 17.1C, Fair Isle 7.7C Lake Vyrnwy 10.3C, Tulloch Bridge -6.3C, Charterhall 0.8 mm, Tiree 13.9h Aberdaron 9.0h Valley 4.3h) [Max 16.1C Min 6.1C Pptn nil]. With high pressure 1028 mb central UK pressure here on the 22nd was on 1027 mb. It was sunny everywhere. The omega block on this occasion almost cloudless (Drumnadrochit 17.9 Gogerddan 16.8C, Wick 8.8C Lake Vyrnwy 11.8C, Kinbrace -6.3C Capel Curig -1.8C, Lerwick 1.4 mm, Rostherne 13.6h Hawarden 13.5h Valley 13.1h ) [Max 15.6 Min 3.7C Pptn nil]. Cilgwyn grass fire, courtesy Snowdonia Mountain Community & BBC.On the morning of the 23rd it was very fine and sunny with 3 oktas of cirrus clouds. Visibility was very good and clear, ozone levels had reduced.. There were contrails to the NE remaining stable, cirrus and cirrostratus clouds increased through the day. At 1542 GMT in a SE'ly Föhn wind of the mountains the temperature rose to 19.8C, highest of the month, with RH typically falling to 24%. High potential evapotranspiration (PE) of 4.2 mm was also recorded by Monsieur Piche's evaporimeter in my Stevenson screen. With a covering of cirrostratus cloud, of the right crystal structure, there was a vivid sun pillar visible after sunset. I spotted this on a photograph (courtesy Snowdonia Mountain Community/BBC) through smoke of a mountain fire at Mynydd Cilgwyn near Carmel, south of Caernarfon. The smoke from the fire was so large that it could be seen from Anglesey where some 999 calls originated. There had been a spate of over 490 irresponsible and illegally lit dangerous grass fires in Wales in the current extremely dry conditions, resulting in a large amount of work for the Fire Service, 20 firefighters attended the Cilgwyn fires (BBC). The Police have set out to trace those who lit the fires (Porthmadog 20.8C, Santon Downham -4.7C Usk -2.3C, Wiggonholt 0.2 mm, Aberdaron 13.8h Valley 11.8h) [Max 19.8C Min 4.8C Grass 0.4 C Pptn nil]. Another nice day on the 24th very fine and sunny, very good visibility and a temperature of 14.8C at 0900 GMT with a weaker Föhn wind lowest RH 36% at 0947 GMT the SE'ly breeze variable and starting to veering towards the north-east. Pressure 1028 mb was rising in high 1034 mb established over the Norwegian Sea. Low 990 mb was over the Atlantic off Iberia. Sticky bud scales were dropping from the trees, there was a mass of bee-flies around a small pool and a holly blue butterfly was seen. High solar radiation today 23.77 MJ m -2 (Porthmadog/ Achnagart 19.5C, Kinbrace -4.9C Bala -1.2C, Baltasound 2.2 mm, Kinloss 13.9h St Athan 13.1h Valley 12.1h) [Max 17.8C Min 6.9C Pptn nil].

Overnight the 'pink' full moon was very bright. Looking out on the adjacent field I could see a herd of black cattle grazing. The movement of their black shapes against the bright moon looked really weird crossing up and down. The morning of the 25th was again very fine and sunny. An E'ly breeze had picked up and it was a cooler 9.6C than yesterday at 0900 GMT. Pressure was steady on 1030 mb with high 1034 mb S North Sea. With low 997 mb off Iberia isobars were being squeezed a little resulting in strong winds along the English Channel. The breeze moderated in the sunny afternoon when it was very pleasant in the garden, the THSW index was 20.6C, but the screened maximum was 14.2C (Porthmadog/ Castlederg 17.9C, Fair Isle 8.7C, Altnaharra -4.2C, no significant rain, St Athan 13.6h Valley 12.5h) [Max 14.2C Min 4.2C Pptn nil]. The smallest touch of ground frost on the morning of the 26th just -0.1C recorded, there was a slight white frost on grass at 08 GMT. The sky had a covering of cirrostratus and a solar halo was observed at 0900 GMT. Temperature 11.2C light SSE'ly breeze very good visibility. A lot of dust collected today much of it raised as the result of local farming work in nearby fields, but there was a patch of Saharan dust over the UK as well (Armagh 17.5C Bala 16.4C, Fair Isle 7.2C Aberporth 10.8C, Topcliffe -3.6C Bala -2.0C, Fyvie Castle 8.8 mm, Bournemouth 13.6h Aberdaron) [Max 15.6C Min 4.1C Grass -0.1C Pptn 0.2 mm]. A change in the weather on the 27th beginning dull with overcast skies, and damp. The first rain for 12 days, just 0.2 mm measured, it had dampened grass and concrete, but the parched soil still looked dry. Pressure 1010 mb had fallen with a low over S Scotland and an occlusion over the Irish Sea. Dull and cold day brightening up in the afternoon with a glimpse of sunshine at 1545 GMT the temperature struggled to reach 11.5C at 1604 GMT (Wisley 18.6C Cardiff 15.9C, Santon Downham -2.8C Usk -0.6C, Leek 9.6 mm Lake Vyrnwy 6.2 mm, East Malling 12.5h St Athan 4.1h) [Max 11.5C Min 7.6C Pptn 1.4 mm]. The 28th was another dull and for a late April day rather cold. The temperature at 0900 GMT was 7.1C and pressure 1011 mb with shallow low 1003 mb over France and a cold air plunge from the north. A showery day, slight morning and afternoon with a little sunshine in between (Santon Downham 15.0C Porthmadog 13.2C, Altnaharra 3.6C, St Athan 30.0 mm, Weybourne 11.4h Aberdaron 2.9h) [Max 11.8C Min 5.2C Pptn tr]. We still had the cold air from he Arctic on the 29th, but it was fine and sunny with very good visibility in clean air. Snow had fallen overnight and a light covering was lying at 2750 ft. Dry and mostly sunny through the day (Usk 13.5C, Kinbrace 4.5C Trawsgoed -1.1C, Thomastown 6.4 mm Hawarden 5.4 mm, Aberdaron 12.6h Valley 11.1h) [Max 10.9C Min 3.2C Pptn 1.5 mm]. The 30th continued on the cool side with Arctic air coming from the region of the Barents Sea via the North Cape. It had no doubt warmed a little on its way, but the 6.2C at 0900 GMT felt chilly on the E'ly breeze. There were cumulus clouds and cumulonimbus in the vicinity. It was cloudy around noon as convection formed overhead, otherwise it was sunny and dry here. It was the wettest day of the month, rainfall 24-h to 09 GMT on the 1 May was 3.6 mm (Cardinham 13.7C Trawsgoed 12.5C, Tulloch Bridge -4.2°C Pembrey Sands -2.4C, Gringley on The Hill 19.0 mm Milford Haven 5.8 mm, Tiree 14.2h Aberporth 13.1h) [Max 10.9C Min 3.3C Pptn 3.6 mm]

A dry month with 16.7 mm rainfall (31%) & [25%] of averages, least since 1980 and ranking 6 in Llansadwrn records since 1828. Wintry at the beginning the mean temperature 7.7C was (+1.6) & [+1.4] of averages, lowest since 2013 and ranked 8 in station records since 1979. It was the sunniest April on record on Anglesey.



Home page Site map Top Home page Site map Top

May 2021

May 1 - began fine and sunny with few clouds, but what cumuli there were were towering over the mainland mountains to the south of the station. There had been a moderate fall of ice pellets around 0315 GMT and the overnight air minimum was 2.7C and -0.8C on the grass. Precipitation was 3.6 mm (credited to the 30th April) and the soil surface looked moist, there was a little snow on the mountaintops. Pressure was on 1018 mb and the day fine and sunny. Two cumulonimbus developed over the mountains in the afternoon. An unseasonable vigorous depression was forecast to develop west of Shannon, Ireland, on the 3rd, the Met Office issued a yellow warning for wind and rain affecting Wales (Gosport 15.0C Usk 14.0C, Shap -5.8C Pembrey Sands -3.1C, Wainfleet 8.6 mm Cardiff 3.0 mm, Manston 13.0h Aberporth 12.6h) [Max 11.9C Min 2.7C Grass -0.8C Pptn 0.1 mm]. Fine and sunny and feeling a little warmer on the 2nd at 0900 GMT. Cannons were firing in the fields today, bird scarers but sounding like from the 1812 overture. Visibility was good, but hazy, I could see no snow on the mountains. Pressure was on 1021 mb within high 1022 mb over the Celtic Sea. Mostly sunny day (Pershore 16.4C Cardiff 15.1C, Tyndrum -4.2C Sennybridge -3.6C, Goudhurst 8.0 mm Rhyl 7.4 mm, Camborne 12.9h St Athan 12.1h Valley 6.4h) [Max 13.9C Min 2.9C Grass -1.3C Pptn 3.3 mm]. The unseasonable vigorous low had arrived on the 3rd, pressure 1009 mb was falling quickly with the deepening low 987 mb W of Malin Head. It was raining and visibility was poor. The SSW'ly soon reached strong to gale-force around the coast Valley f9 and gusting 63 mph, and over high ground Capel Curig 66 mph with 56 mph recorded in Llanfairfechan Gorddinog and 50 mph recorded at Gorwel Heights. Rain was moderate to heavy and very heavy at 1500 GMT falling at a rate of up to 20 mm/h. Rainfall 24-h from 0900 GMT today was 27.5 mm, more in a day that what we had in April. Later the sky cleared and there was a little sunshine before the end of the day (Shoeburyness 14.0C Hawarden 12.1C, Kinbrace -5.9C, Capel Curig 50.8 mm [65.6 mm, most in Europe today] Rhyl [26.0 mm], Kirkwall 7.0h Valley 1.6h) [Max 10.9C Min 6.5C Pptn 27.5 mm]. The morning of the 4th was very wet after 27.5 mm of rain slaking the dry soil of April. Milder, no air frost reported. The ground was covered with shredded leaves and flowers off the horsechestnut trees the result of yesterday's strong winds. The rain soon eased and the sky began to clear. Becoming bright with the wind moderating and a mostly sunny afternoon (Pershore 15.3C Cardiff 13.6C, Dalwinnie 0.7C, Blencathra 33.0 mm Capel Curig 23.4 mm, Kirkwall 9.6h Valley 7.8h) [Max 11.6C Min 5.1C Pptn 2.6 mm].

Bluebell wood in May.

Showers of ice pellets here after midnight (02 & 06 GMT) on the 5th with snow falling on the mountains, a light cover at 2000 ft with some as low as 1850 ft. We were into another cold plunge from Arctic regions, we were north of he jet stream currently over France, and there was a shower trough over Anglesey. The sky was mostly covered with towering cumulus clouds, a cumulonimbus was in the vicinity. There was a shower of snow pellets at 1108 GMT, conical 4-5 mm diameter. Frequent brief sunny spells and a light shower of rain in the afternoon (Heathrow 14.4C Llansadwrn/ Pembrey Sands 12.0C, Warcop -3.1C, Swyddffynnon 12.6 mm, Morecambe 14.1h Aberdaron 8.1h) [Max 12.0 C Min 2.4C Grass -1.3C Pptn 1.5 mm]. Further showers of ice pellets overnight and on the morning of the 6th at 08 GMT. There had been a fresh fall of snow on the Snowdonia Mountains and was lying lightly at 2000 ft on the northern slopes of the Carneddau and there was some at the head of the Ogwen valley at 1250 ft earlier. A few cumuli and a cumulonimbus at first with showers on the mountains, mostly good visibility and a chilly N'ly breeze. Fine, with cloud developing later with frequent sunny spells (Plymouth 14.3C Usk 14.0C, Eskdalemuir -5.5C Lake Vyrnwy -0.8C, Altnaharra 32.0 mm Gogerddan 6.4 mm, Aberdaron 13.5h) [Max 11.9C Min 0.7C Grass -2.4C Pptn 0.4 mm]. Looking out early on the 7th across the fields I could see a white frost on the grass, the cattle were not happy about that, but it soon melted. Before 0900 GMT there were showers that included small ice pellets. Visibility was moderate to good, there were remnants of snow above 2750 ft on the mountaintops. The morning was mostly cloudy and being north of the jet stream that was over France, we had cooler air. The W'ly breeze backed NE during the day. Frequent sunny spells in the afternoon with a slight shower of rain; a snow shower covered Carnedd Llewelyn completely white (Heathrow 15.7C Cardiff 15.3C, Topcliffe -4.4C Bala -2.6C, Scarborough 9.6 mm Hawarden 1.0 mm, Morecambe 12.8h Aberdaron 11.8h) [Max 12.5C Min 1.2C Grass -2.7C Pptn 16.4 mm]. With the NE'ly backing S'ly and strengthening wind a band of moderate to heavy rain arrived at 0230 GMT on the 8th, heaviest 5 mm/h at 0717 GMT. At 0900 GMT when 16.4 mm was measured it was still raining, visibility was moderate to poor. Dull and wet, one of those days set aside for being indoors. The rain was heaviest 6.2 mm/h at 1015 GMT with the wind peaking at 29 mph about 1239 GMT. The afternoon was dull, but dry (Manston 18.3C Hawarden 15.3C, Tulloch Bridge -4.2C, Libanus 52.2 mm, Kirkwall 4.4h Valley 1.0h) [Max 14.7C Min 4.6C Grass 1.6C Pptn 5.0 mm]. After early fog around he coast the morning of the 9th was fine and bright, but very windy. There were 6 oktas cover of cumulus and cirrus clouds, the S'ly wind blowing force 5/6. Pressure was on 991 mb with filling low 972 mb Shannon. There was a cold front lying along the spine of the Britain pressure was high 1027 mb at the tip of Greenland and over SE Europe (Santon Downham 22.5C Hawarden 17.7C, Tain Range -0.1C, South Uist 19.0 mm Tredegar 186 mm, Weybourne 8.0h Aberdaron 6.4h) [Max 14.4 C Min 9.5C Pptn 1.4 mm].

A fairly mild night the air minimum 9.6C on the 10th and a showery morning. Bright with glimpse of sunshine and light showers of rain. Pressure little changed at 991 mb with the anchored Shannon low 981 mb dominating the weather. Very windy again the SW'ly near gale force with strong gusts in the afternoon, slight showers here, heaviest in Llanfairfechan and across the mountains. The showery airflow was from Arctic regions via the Atlantic so not quite as cold as it might have been (Cromer 17.9C Hawarden 17.4C, Tain Range 3.2C Hawarden 6.5C, Fair Isle 13.8 mm Tredegar 11.8 mm, Shoeburyness 9.8h Hawarden 5.9h) [Max 12.9C Min 9.6C Pptn tr]. Would you believe it? The Shannon low is well anchored and hadn't moved far on the 11th, but filled to 993 mb pressure here 1005 mb was rising. There was a drying S'ly breeze, concrete and grass were dry, the soil surface drying was not quite dry. Fine with good hazy visibility in the morning. The greens of newly emerged leaves in the wood at Gadlys, Llansadwrn.Cumulus clouds were well developed and getting darker when thunder was heard from 1150 GMT. Isolated near claps and a distant continuous rumble went on for 30 minutes. Sferics indicated isolated lightning near Penmon and severe storms further east, over 1000 strikes were recorded in Wales today. Heavy showers of hail (snow pellets) occurred in places something described by some as 'biblical'. At Bala the ground was covered white in a significant fall. In the wood the newly emerged bright green leaves are quickly closing the canopy and soon the bluebells will fade (St James Park 18.2C Whitechurch 15.6C, Shobdon 1.7C Trawsgoed 3.7C, Eskdalemuir 20.2 mm Bala 15.0 mm, Katesbridge 13.5h Aberdaron 11.7h Valley 9.9h) [Max 12.2C Min 7.8C Pptn 4.1 mm]. Overcast and dull on the morning of the 12th with moderate rain and very poor visibility. Low-pressure associated with anchored low 1002 mb Shannon was responsible for the poor weather. An occluded front lay across Cardigan Bay. The rain stopped during the morning and the afternoon turned out sunny. Six dozen broad been plants raised in the greenhouse were planted out yesterday, the rain had watered them in nicely and they were standing well Santon Downham 17.9C Hawarden 16.0C, Katesbridge -1.0C Tredegar 2.2C, Aboyne 24.0 mm Valley 1.2 mm, Weybourne 10.9h Aberdaron 8.2h (Santon Downham 17.9C Hawarden 16.0C, Katesbridge -1.0C Tredegar 2.2C, Aboyne 24.0 mm Valley 14.2 mm, Weybourne 10.9h Aberdaron 8.2h Valley 2.8h) [Max 13.7C Min 5.8C Pptn 3.9 mm]. Growth of cereal grop since sowing on 21 April 2021 at Gadlys, Llansadwrn.The 13th began brightly with a covering of 6 oktas cumulus, altocumulus and cirrus clouds. It had been calm overnight, there was now a gentle breeze from the north-east. A low 1002 mb Isle of Wight produced a local disturbance affecting S Wales and S England with some large falls of rain. The morning here slowly turned cloudier, middle of the day was brighter with a little sunshine, Max 14.2C highest in Wales, then cloudier with a light shower in the afternoon (Ballywatticock 17.2C Llansadwrn/ Mona 14.2C, Okehampton 8.2C Aberporth 9.5C, Katesbridge -2.2C Capel Curig 1.9C, Liscombe 41.2 mm Libanus 31.8 mm, Camborne 11.6h Valley 2.9h) [Max 14.2C Min 5.3C Pptn 0.3 mm]. A miserable start to the 14th, dull and quite dark with slight rain and drizzle. Amounts of precipitation have been very small, but it makes for a poor day in May. Low 1006 mb was situated near Calais this having an associated occlusion over Wales. Rainfall so far this month totals 66.5 mm, up to the May averages. In addition it has been cold, the May mean temperature so far 8.6C 3 degrees below normal. There were widespread patches of light rain over Britain this morning, the weather is not good for May. The jet stream is to the S of Britain over much of Europe and N Africa this driving very unseasonable weather across much of Europe and the Med, with no early end in sight on the forecast models. The afternoon was drier with glimpses of sunshine (Trawsgoed 16.6C Llansadwrn 15.1C, Katesbridge -1.6C, Swyddffynnon 19.2 mm, Tiree 7.9h Valley 6.1h) [Max 15.1C Min 7.8C Pptn 2.5 mm]. It was raining continuously on the morning of the 15th when it was calm at 0900 GMT. Visibility was moderate in rain and mist, the light level was 165 W. Pressure 999 mb was falling with low W of Ireland 985 mb filling 988 mb at noon. The day kept cloudy with rain at times, no good for an work in the garden. Heavy rain at Gorwel Heights around 20 GMT fell up to 30 mm/h (Achnagart 16.5C Cardiff 15.7C, Loch Glascarnoch 0.2C, Swyddffynnon 25.8 mm, Stornoway 12.6h St Athan 6.9h Valley 1.8h) [Max 15.2C Min 7.3C Pptn 3.8 mm].

The first 15-days temperatures were again well below normal the mean temperature 9.2C (-2.6) & [-2.5]. In contrast to the beginning of April it was very wet with precipitation 72.7 mm (108%) & [107%] of averages. Sunshine had averaged 6.4 h per day, the sunniest day on the 3rd with 12.7h.

The 16th began fair and bright with some weak sunshine. It had recently been calm, nut at 0900 GMT there was a light SSE'ly breeze setting in. It felt warmer, the temperature 12.5C and the soil surface was 15.0C. There were dark looking cumulus clouds nearby and cumulonimbus in the vicinity. Pressure was steady on 996 mb with low 992 mb over the Celtic Sea and detached occlusion charted over the Irish Sea. Since the nice sunny weather at the end of April the barometer has shown unsettling falls within the low-pressure area north of the Jet Stream. There were rain showers over S Britain, heavy over S England, today it was fine and sunny in Scotland. Showers developed in the morning, the afternoon was dry and sunny, but moderate showers fell in Llanfairfechan. Clouds cleared away by evening that was very fine and sunny (Myerscough 18.1C Hawarden 17.1C, Aboyne -0.7C, Okehampton 31.6 mm Libanus 26.0 mm, Tiree 12.8 Aberdaron 10.6h Valley 7.2h) [Max 13.7C Min 7.4C Pptn 1.1 mm]. A bright morning on the 17th after early slight showers of rain, but at 0900 GMT convective cloud was building. Many cumulonimbus clouds developed over England with heavy showers and lightning in places, but here the clouds diminished to fair weather cumuli and we had a fine, dry and sunny afternoon the temperature reached 16.2C highest of the month so far, despite a light sea breeze off Traeth Goch in the afternoon, and clear evening. (Pershore 18.0C Usk 17.1C, Katesbridge -0.9C Bala 2.5C, Wych Cross 16.4 mm Rhyl 5.2 mm, St Athan 11.2h Valley 9.9h) [Max 16.2C Min 7.6C Pptn nil]. It was fine and sunny early on the morning of the 18th, but by 0900 GMT it had become cloudier. Visibility was very good. Later clouds diminished and the afternoon was mostly sunny and the day dry. Grass had grown more in the last week with increased temperatures (still 2 degrees below normal) and more than adequate moisture and had grown at a rate of 5.9 g dry mass m -2 d -1 (59 kg ha -2 d -1 ) , but was still low in comparison to previous years (Hull 17.9C Cardiff 16.3C Llansadwrn 16.2C, Katesbridge -1.1C, Coleshill 22.0 mm Libanus 9.2 mm, Morecambe 13.3h Aberdaron 8.8h) [Max 16.2C Min 7.6C Pptn nil]. Cistus var Sunset flowering in our garden at Gadlys, Llansadwrn.A bright and fine morning on the 19th and 12.3C with a light W'ly breeze the soil surface was drying nicely. There was a minor ridge of high-pressure from Spain over the Celtic Sea with pressure here 1018 mb rising. There was a northwards bulge in the Jet Stream with unseasonably windy weather affecting S England and S Wales. The Meto had issued a yellow warning for strong winds, this was later was upgraded to include N Wales wind and rain. Cistus var Sunset flowering in our garden at Gadlys, Llansadwrn.The pink Cistus var Sunset acquired from Dundee Botanic Garden (right) drops its petals on to the grass every evening (left) and produces new flowers every morning. The afternoon was quite sunny and warm, spent some time tying up garden plants ahead of the strengthening winds (Pershore 18.3C Usk 17.0C, Eskdalemuir -1.7C Bala 0.9C, Aboyne 12.6 mm Usk 3.0 mm, Aberdaron 12.5h Valley 11.8h) [Max 15.2C Min 6.9C Pptn 0.8 mm]. As forecast the 20th was a very wet and windy day. Squally showers of rain before 0900 GMT, I was lucky there was a lull when making the observations, but then more rain as the SSE'ly wind began to pick up. Pressure 1006 mb was falling rapidity with Atlantic-low 983 mb just off SW Ireland. It was particularly bad at 1415 GMT with a mighty squall and heavy rain. Snowdonia was the wettest place in Europe today with 83.4 mm recorded at Capel Curig, here I recorded 35.2 mm, Valley reported gales with a peak gust of 57 mph (Chertsey 15.3C Cardiff 15.0C, Ravensworth 0.7C, Capel Curig 44.2 mm [83.4 mm], Boulmer 4.2h Wales nil) [Max 11.4C Min 8.1C Pptn 35.2 mm]. A rough night and not a lot improved by the morning of the 21st when covered with low cloud it was raining moderate to heavily. During the morning the rain turned increasingly towards drizzle with very poor visibility. There was much debris on the ground, twigs with new leaves and flowers off Horsechestnut and beech trees, what a mess. Pressure was at its lowest 984.6 mb at 0337 GMT and was rising 986.9 mb at 0900 GMT. The low past over the isle of Man and was over Morecambe Bay on track for the North sea. The 20th and 21st had been two quite cold days for the time of year, today the maximum 11.1C. Rainfall to date was 110 mm this chasing the wettest May on record with 148.3 mm in 2003 Squally showery rain continued into the evening (Myerscough 15.4C Hawarden 13.0C, Baltasound 3.4C, Capel Curig 66.2 mm, Lerwick 10.2h Wales nil) [Max 11.1C Min 8.9 Pptn 8.7C]. After another cool night it was a bright start on the morning of the 22nd with the cloud clearing with glimpses of sunshine between dull spells of drizzle . Pressure 1004 mb was rising along with the temperature 9.1C after 6.8C in the small hours. The low of recent days was 987 mb mid North Sea on the way to the Baltic Conditions were right for ice precipitation on the mountaintops of Snowdonia. Scattered clouds clearing in the afternoon with views of the mountains where ice precipitation of Crib-y-ddysgyl and Carnedd Dafydd was seen (Kew Gardens 15.9C Cardiff Bute Park 15.0C Gadlys Gardens 13.1C, Braemar -0.1C, Okehampton 22.0 mm Scolton 6.2C, Prestwick 11.9h Valley 9.4h) [Max 13.1C Min 6.8C Grass 6.3C Pptn 1.7 mm]. The 23rd began wet and blustery with pressure 1003 mb falling with low 987 mb S of Iceland W of Scotland. Low 997 mb had reached the Baltic. A showery trough was over Wales too wet to do gardening work. Rhosneigr was very busy with water sports the kite board surfers taking advantage of the force 5 SSW'ly wind with moderate waves (Coningsby 15.2C Hawarden 13.1C, Lake Vyrnwy 7.9C, Altnaharra -3.2C Sennybridge 2.3C, Capel Curig 26.6 mm, Lerwick 11.7h Valley 0.6h) [Max 11.3 Min 7.5C Pptn 13.8 mm]. A disappointing beginning to the 24th after another cool and wet night. Light rain had just stopped in time for the 0900 GMT obs, but soon started up again. The soil was very wet with small puddles in places. The rain eased during the morning and by noon the sun was breaking through. Pressure 1001 mb was rising, there was a complex low-pressure area over Britain with 992 mb Aberdeen and 998 mb Pembrokeshire Islands. A pleasant afternoon in Beaumaris that was 'heaving' with people unusual as it was a Monday visiting after the easing of COVID-19 lockdown. Castle Square was particularly busy with people sitting in the Square and standing around at the Castle enjoying the sunshine in a little more freedom. A clear sunny evening (Hull 16.7C Cardiff 15.2C, Castlederg -0.5C Trawsgoed 2.9C, Dalwhinnie 30.2 mm Porthmadog 10.2 mm, Thomastown 10.6h Valley 7.6h) [Max 14.7C Min 6.4C Grass 4.4C Pptn 1.8 mm]. A bright morning on the 25th with pressure rising with pressure rising. High-pressure off Iberia over the Atlantic had a ridge extended towards Iceland. Pressure was low 983 mb over Greenland and high 1031 mb N of Svarlbard. Quite a nice day, the soil was still wet, and a bit drier in the afternoon when I planted six dozen lettuce plants of four varieties raised in modules in the greenhouse. I hope the slugs won't eat them all, I grow them quite large small ones tend not to survive an attack (Pershore 17.1C Cardiff 15.2C, Castlederg 3.5C, Leconfield 21.2 mm Cardiff 6.4 mm, Katesbridge 12.0h Valley 12.0h) [Max 15.7C Min 7.4C Pptn 0.4 mm].

The 26th began fine, bright with a cool NNE'ly breeze. There was still a pool of cool air originating in Arctic regions over the North Sea and the UK. Pressure was steady on 1017 mb with low 999 mb Denmark and high 1024 mb Biarritz. Visibility was very good and the sky soon clearing gave a mostly sunny day (Killowen 18.6C Usk 18.2C, Machrihanish 1.0C, Drumalbin 10.6 mm Capel Curig 1.4 mm, Valley 15.4h) [Max 15.1C Min 7.4C Rain nil]. . Very fine and sunny on the morning of the 27th with a veil of cirrus clouds and a few small cumulus over mountains to the south. Visibility was very good and clear, there had been a heavy dew with the grass minimum down to 3.5C. It was warmer with 15.1C at 0900 GMT, it turned cloudy just before and after noon, rising to 18.2C in the afternoon. A solar halo was seen widely in parts Britain. There was light rain before midnight (Wisley 22.0C Hawarden 20.6C, Sennybridge -0.5C, Derrylin Cornahoule 4.2 mm Milford Haven 0.8 mm, Bournemouth 14.7h St Athan 12.9h Valley 11.4h) [Max 18.2C Min 6.1C Grass 3.5C Rain 2.1 mm]. The Welsh poppies were hanging their heads in the rain in our garden at Gadlys.Light rain continued after midnight on the 28th, heaviest around 0130 GMT, it was still raining slightly at 0900 GMT when it was misty with moderate visibility. It was a dull, humid and wet day with light to moderate rain in the afternoon heaviest between 14-15 GMT. Sunless (Achnagart 22.1C Cardiff 19.7C, Kinbrace 0.8C. Lough Fea 7.2 mm Milford Haven 7.0 mm, Lerwick 15.2h Aberdaron 0.4h) [Max 14.9C Min 9.9C Grass 9.2C Rain 1.8 mm]. The sky was overcast on the morning of the 29th, dull and calm with good hazy visibility. Pressure 1027 mb was rising and it cleared up late in the afternoon, the evening was sunny (Chivenor 22.9C Cardiff 22.1C, Balmoral 2.1C Mona 10.0C, Sennybridge 2.0 mm, Weybourne 15.1h St Athan 4.6h) [Max 15.8C Min 10.8C Rain nil]. The 30th began very fine, sunny and warm! It was 20.1C at 0900 GMT with not much in the way of clouds, so a blue sky. There were a few cumuli to the S over the Snowdonia Mountains. There was heavy dew on the grass, but this soon dried in the warmth and a light NE'ly breeze. A sunny and warm afternoon in Llanfairfechan Gorddinog 23.3C Gorwel Heights 23.1C (Achnagart 24.0C Porthmadog 23.6C, Altnaharra 1.6C Sennybridge 4.2C, no significant rain, Stornoway 15.9h Aberdaron 15.4h Valley 13.0h) [Max 21.9C Min 10.6C Grass 6.5C Rain nil]. Another fine morning on the 31st the temperature at 0900 GMT 18.7C and again a mostly blue sky, some cumuli were bubbling over the mountains. A warm mostly sunny day (Kinlochewe 25.1C Cardiff 23.4C, Shap 2.2C Bala 4.2C, no significant rain, Morecambe 15.8h Valley 14.4h) [Max 21.3C Min 10.2C Grass 5.7C Rain nil].

A wet month with 140.3 mm rainfall (208%) & [207%] of averages, most since 2015 ranked 3 in Llansadwrn records since 1828. Wintry at the beginning of the month the mean temperature 10.5C was [(-1.2)] of averages, lowest since 2015 ranked 6 in station records since 1979. Not up to the record sunshine of last May, but one of the 30 sunniest on the Anglesey record since 1931.



Home page Site map Top Home page Site map Top

June 2021

June 1 - warm and mostly sunny the temperature at 0900 GMT 21.2C this rising to 24.2C at 1513 GMT (Cardiff 26.1C, Boulmer 10.9C Lake Vyrnwy 21.1C, Aboyne 3.6C Usk 7.9C, Lerwick 15.6h St Athan 14.0h Valley 9.3h, South Uist 0.8 mm Wales nil) [Max 24.2C Min 12.8C Rain nil].

June the month of flowering Rhododendrons in our Gadlys garden.

A cloudier morning on the 2nd the sky a mixture of cirrus, altostratus and lenticular altocumulus, 6 oktas at 0900 GMT. Visibility was good, but very hazy with moderate levels of pollution smoke up to 138 µ per m-3 ozone recorded at at Marchlyn Mawr (Welsh Air Quality Forum), the result of increased traffic due to easing of lockdown and sunny weather. Cloud increased in the afternoon becoming quite dark under thickening clouds. Showery rain from about 15 GMT when gave up working in the garden turning moderately heavy at 1620 GMT (Cardiff 26.1C, Aboyne 3.6C, South Uist 0.8 mm. Lerwick 15.6h St Athan 14.0 Valley 4.2h) [Max 22.9C Min 13.7C Rain 3.2 mm]. Pink Rhododendron flowering in our garden at Gadlys.It had been mild overnight the air minimum 12.4C and on the grass 12.3C, bright the broken cumulus clouds increasing on the 3rd at 0900 GMT. It was 14.9C and a frontal wave low 1009 mb off NW Ireland had unsettled the weather, but pressure 1014 mb was rising. Ozone levels remained moderately high the visibility good, but hazy. The morning was dull and breezy, but then brightened up in the afternoon with spells of sunshine after 13 GMT (Santon Downham 24.7C Cardiff 19.8C, Braemar 3.4C Libanus 10.4C, Stormont Castle 15.8 mm Mona 4.6 mm, Kirkwall 15.5h Valley 8.5h) [Max 17.0C Min 12.4C Grass 12.3C Rain nil]. On the 4th visibility had improved and it was very good and clear. Cooler the air minimum 8.7C and 5.7C on the grass. Pressure 1024 mb was rising in a slack area over the UK, pressure was 1025 in Norway. Very fine with broken cloud decreasing it was a dry mostly sunny day. With low 1019 mb N France it was a wet day in SE England [Hereford 20.8C Bala 2.8C Shoeburyness 22.0 mm Valley 15.7h] [Max 17.9C Min 8.7C Grass 5.7C Rain nil]. The sky was almost clear at dawn on the 5th with 4.0C on the grass no good at all for young sensitive vegetable plants that are looking a bit yellow, but before 0900 GMT cloud had encroached it was overcast and the air temperature 15.1C and the soil 15.4C at 5 cm depth, temperature fluctuations can cause flower bud drop. There was an occlusion over Ireland and the Celtic Sea and cloudiness was affecting the western fringes again, we had slight drizzle at times through the day (St James Park 24.0C Hawarden 22.5C, Eskdalemuir 1.5C Bala 3.4C, Thomastown 5.2 mm Pembrey Sands 4.4 mm, Dyce 15.8h Hawarden 9.6h Valley 3.8h) [Max 18.7C Min 8.2C Grass 4.0C Rain trace].

The 6th began brightly the sky mostly clear at dawn, but cloud had had increased and by 0900 GMT it was dull. There was a cool feeling NNE'ly breeze and visibility was very good. Pressure was on 1026 mb in a ridge from high 1019 mb over the Atlantic off Iberia, while complex low-pressure 998 mb lay S of Iceland. Some glimpses of sunshine during the morning, cloudier at noon, the sunny spells later. Planted out 4 dozen sweetpea plants raised in the greenhouse (St James Park 23.4C Cardiff 23.0C, Katesbridge 4.0C Whitechurch 6.2C, Llysdinam 13.4 mm, Morecambe 14.8h Valley 10.9h) [Max 17.7C Min 10.3C Rain trace]. Iris sibirica and Asphodelus alba flowering in our garden at Gadlys. A fine and dry morning on the 7th although there had been moderate dew on the grass the minimum thermometer reading 5.9C still on the cold side for sensitive garden plants. Cloud was decreasing and the WSW'ly breeze was strengthening. Weather fair, becoming brighter with sunny spells and moderate breeze. Planted out climbing French beans raised in the greenhouse, watering of potted garden plants and some vegetables on the plot took a while as there had been little rain. The soil surface is dry and cracked (Coningsby 24.6C Hawarden 22.2C, Tyndrum 0.9C Whitechurch 5.3C, Waddington 12.6 mm, Manston 14.4h Bala 7.7h Valley 7.3h) [Max 16.8C Min 9.9C Grass 5.9C Rain nil]. Very fine, bright and breezy on the morning of the 8th and feeling warmer the temperature 16.6C. Pressure steady on 1-23 mb with high 1025 mb Netherlands. There was an occlusion over the North Channel associated with low 1001 mb N Iceland. A fair day, dry with a little sunshine at times. Prepared a special bed on the vegetable plot for hardening off courgette and marrow plants raised in the greenhouse (St James Park 24.8C Hawarden 23.5C, Okehampton 4.3C Usk 5.4C, Dundrennan 1.2 mm, Shoeburyness 15.0h Hawarden 12.6h Valley 2.1h) [Max 18.8C Min 11.0C Rain nil]. Overcast sky on the morning of the 9th, fine and breezy with moderate to good visibility. Pressure was on 1019 mb with low 983 mb SE Greenland with frontal bands over western fringes. It felt warm in the 16.2C (dewpoint) 14.5C) at 0900 GMT. The sky appeared brighter at times when there was a little weak sunshine. It was breezy with the SSW'ly force 5 noisy in the now fully leafed tall trees. There was a shower of rain in the afternoon (Hull 26.4C Cardiff 23.3C, Bournemouth 5.3C Bala 6.4C, Achnagart 18.4 mm Capel Curig 6.6 mm, Wattisham 15.2h Hawarden 6.8h Valley 0.0h) [Max 17.9C Min 12.0C Rain 0.3 mm].

Another dull sunless day on the 10th beginning with slight rain and graduation on to intermittent slight rain and drizzle. Cloud was hugging the mountaintops of Snowdonia and visibility was just good in the misty rain. Fog was around coastal areas. Continuing mild the 16.4C 93% RH at 0900 GMT rising to 17.9C at 1437 GMT. There was a partial eclipse of the sun (31%) visible in theory here today beginning around 0915 GMT. Nothing of it was seen here, but folk saw it from clear sky places in England. I had set up a full array of met instruments just in case, they detected little. Very disappointing. In 1999 I had an interesting set of readings on the 11th August for the 91% partial eclipse. Observations showed a 98% fall in solar radiation and a fall in temperature, measured by shielded thermometers within a Stevenson screen, of 2.1C 25 min after maximum partiality. Relative humidity, also measured in the screen, increased from 76% at 0900 GMT to 90% 15 mins after maximum partiality. An unshielded temperature probe exposed at 2.4 m and the grass minimum thermometer at 2 cm above grass registered falls of 4.2C and 7.5C respectively, only 5 mins after maximum partiality. The temperature of the soil in a bare plot at a depth of 5 cm fell 0.3C after 30 min. At this, and some other depths, the normal daily rise in temperature was depressed. Dispersion of cumulus clouds took place during the event and reformed again afterwards. The quality of the light was seen to change and become a bluish white colour. Shadows became sharper and some birds started to sing. Read my account here Eclipse 11 August 1999 (Heathrow 24.7C Hawarden 24.2C, Harris Quidnish 11.0C Aberdaron 11.8C, Capel Curig 15.8 mm, Shoeburyness 12.9h Hawarden 4.8h valley 0.0h) [Max 17.9C Min 13.1C rain 1.3 mm].

The 11th would have been no good to view the eclipse beginning with low cloud, driving drizzle in the force 5 SW'ly and fog at 0900 GMT, occurs rarely at this time here, RAF Valley was on RED since 0720 GMT. The wind moderated through the morning and the afternoon was drier and a little brighter (Heathrow 25.6C Hawarden 21.5C, Stornoway 10.7C Lake Vyrnwy 11.9C, Capel Curig 11.2 mm, Sheffield 7.9h Hawarden 3.4h Valley 0.9h) [Max 16.0C Min 13.0C Rain 0.1 mm]. A corner of our garden at Gadlys with London pride in flower.The morning of the 12th began mostly cloudy, but the low cloud and mist soon began to lift albeit rather slowly. Pressure 1025 mb was rising in a high 1026 mb over the Celtic Sea. A sunny afternoon (Kew Gardens 24.8C Gadlys Gardens 19.1C, Spadeadam 6.2C Whitechurch 6.9C, Baltasound 2.6 mm, Almondsbury 14.5h Aberdaron 12.2h Valley 8.8h) [Max 19.1C Min 10.3C Rain nil]. A very fine, sunny and warm morning on the 13th with very good clear visibility. There was just a little cloud overhead the station and the temperature at 0900 GMT was already 18.9C No rain, all surfaces were dry. Several butterflies were seen in the garden including 4 small tortoiseshell, 1 each of painted lady and speckled wood. Many bumblebees were buzzing around, they have a good choice of flowers and clover, I was pleased to see some working over the broad beans on the vegetable plot too (St James Park 28.0C Cardiff 27.4C Gorwel Heights 25.3C , Santon Downham 6.4C Sennybridge 6.9C, Achnagart 12.6 mm, Weybourne 15.7h Aberdaron 15.5h Valley 10.8h) [Max 23.1C Min 12.7C Rain nil]. The 14th began fine, but dull. Still no rain everything very dry. Pressure 1022 mb was rising in a ridge to the SW from high 1020 mb Azores. Deep low 978 mb was S Greenland and there was a cold front over N Wales. Brighter in the afternoon with some sunny spells (Teddington 29.7C Cardiff 24.4C, Altnahinch Filters 7.6C, Dunstaffnage 16.0 mm Rhyl 0.4 mm, Bournemouth 13.5h St Athan 12.2h Valley 5.6h) [Max 17.7C Min 13.3C Rain nil]. After a cool night the 15th was very fine and sunny with very good visibility. Pressure was on 1022 mb with the ridge declining as a ,low 979 mb edged close to the W of Scotland. Sunny at times in the afternoon planted out rows of purple sprouting broccoli and kale from the greenhouse. Set up mats around the stems and covered plants with netting to protect from cabbage root flies and white butterflies. Time consuming, but necessary to get a good crop, watered them in as the soil was very dry (Heathrow 26.6C Cardiff 24.6C Gorwel Heights 23.2C, Aboyne 1.9C Bala 3.4C, Dunstaffnage 14.2 mm, 14.8h St Athan 14.2h Valley 10.6h) [Max 20.6C Min 8.4C Rain trace].

The first 15-days temperatures were above normal for the first time in a while the mean temperature 19.1C (+1.0) & [+1.2]. In contrast to May it had been dry 14.3 mm (17%) & [19%] of averages. Sunshine at RAF Valley had averaged 6.6 h per day with 15.7h on the 4th.

I was hoping for a fine day today the 16th as had been informed by SP Energy that the electricity supply would be off from 0900 BST to perhaps 1630 BST. The electricity went off on the button and it wasn't a fine day so the weather station computers were offline. The automatic station is powered by solar energy with rechargeable battery backup for the hours of darkness so that continued to record the data that was downloaded when the mains supply resumed. A day in the garden would have been good, but the day was cloudy, dull and sunless with slight rain and drizzle. I tended the greenhouse and made do with a few jobs inside, that without lights was quite dark. No watering of the garden required (Heathrow 29.2C Cardiff 24.0C, Exeter 6.8C, Millport 19.0 mm Capel Curig 5.2 mm [4.6 mm], Ross-on-Wye 12.8h St Athan 12.3h Valley nil) [Max 15.9C Min 12.8C Rain 9.4 mm]. The 17th began fine and sunny with a light NNE'ly breeze after clearing overnight sky and a 5.9C on the grass. Pressure was high 1030 near the Azores. Plants had perked up on the herbaceous borders and vegetable plot. Soil was wet, but cracks in the surface of the undisturbed Met plot had not closed. Pressure 1013 mb was rising with low 998 mb SE Iceland. A cold front was situated over central England while an occlusion was over Ireland. A mostly sunny and dry day. Warm and very wet in Thanet (Manston 24.0C Usk 21.7C, South Uist 13.8C Aberporth 14.7C, Katesbridge 3.0C, Manston 47.8 mm Usk 0.8 mm, Valley 15.0h) [Max 19.5C Min 9,8C Rain nil]. Pressure was steady 1020 mb on the 18th with a low 1007 mb over Brittany. Broken cloud at first with good though hazy visibility. There was a light to moderate NNE'ly breeze, but the sun was breaking through and the afternoon with almost clear sky pleasant with the temperature reaching 16.6C and the breeze moderating (Plymouth 23.3C Porthmadog 21.4C, Loch Glascarnoch 1.7C Trawsgoed 3.9C, Otterbourne WW 67.6 mm, Valley 15.1h) [Max 16.6C Min 8.4C Rain trace].

A very dull morning on the 19th with rain in sight and moderate visibility at 0900 GMT. Pressure 1015 mb was falling as deepening low 997 mb W of Shannon tracked SE towards the Celtic Sea 993 mb by 1800 GMT reaching 1010 mb here. A day of sunshine and slight showers of rain or drizzle clearing by late afternoon when sunny (Blackpool 22.4C Porthmadog 21.5C, Katesbridge 0.4C Tredegar 6.7C, Exeter 9.8 mm St Athan 2.8 mm, Leeming 9.4h Bala 5.7h) [Max 19.8C Min 9.8C Rain trace].

The herbaceous border in our Gadlys garden in June.

On the 20th with the low 98 mb over the Bay of Biscay pressure here was on 1009 mb. The morning was very fine with a cool breeze and with the sky composed on altocumulus and some altostratus clearing it was soon sunny. Visibility was very good and clear. North Irish Sea coastal areas all had a mostly sunny day (Armagh 21.7C Porthmadog 21.0C, Shap 4.7C Lake Vyrnwy 8.1C, Dunstaffnage 14.8 mm Cardiff 12.2 mm, Valley 13.1h) [Max 18.1C Min 12.2C Rain nil]. Pink spotted Cistus, The Herbalist rose, colourful Lupins.The NNE'ly breeze felt cool at 0900 GMT on the 21st, the longest day and it did not feel like the first day of summer. Stratocumulus clouds hung rather low on the mountains of Snowdonia and visibility was moderate to good. Pressure 1016 mb was rising with a ridge between Iceland and N Scotland extended from Azores high 1030 mb. The air was coming from Arctic regions and the cloud associated with the occluded front lying over S Ireland, the Isle of Man and on to the North Sea resulted in a rather dull day. It kept dry here, but there was rain along the entire S coast of England (Gogerddan 20.8C, Wych Cross 11.8C Aberporth 15.1C, Drumnadrochit 1.1C, Plymouth 21.6 mm Cardiff 2.0 mm, Aldergrove 15.2h Aberdaron 4.5h Valley 1.3h) [Max 16.4C Min 11.0C Grass 7.2C rain nil]. A warmer very fine and sunny morning on the 22nd with pressure steady on 1024 mb in a ridge from Azores high 1033 mb. A few cumulus clouds overhead dissipated later. There were lots of bumble bees around the garden, some were doing a good job on the broad beans and others making use of the abundant white clover on grassy areas. I set up the poles for runner beans on the vegetable plot grown in pots in the greenhouse and hardening off outside. A frontal cloud associated with E Icelandic low 998 mb lying to the NW off Ireland and Scotland that was likely to arrived here tomorrow (Aboyne 21.4C Porthmadog 19.6C South Uist 12.8C, Altnaharra -2.4C Bala 3.1C, Goudhurst 10.0 mm, Morecambe 15.5h Valley 13.1h) [Max 18.3C Min 9.4C Grass 6.8C Rain 0.8 mm]. The 23rd began overcast with a warm front over the Irish Sea. There was light rain, moderate at 0900 GMT, and it continued slight to moderate intermittently through the dull and sunless day. It seemed to be raining all day, the AWS recorded rain duration was 13h 09-09 GMT (Leuchars 23.4C Cardiff 21.0C Aberdaron 12.2C, Ravensworth 1.0C Bala 1.3C, Ballypatrick Forest 8.6 mm Aberdaron 5.6 mm, Weybourne 15.2h St Athan 10.5h Valley nil) [Max 15.4C Min 7.9C Grass 5.0C Rain 5.6 mm]. Conditions were reminiscent of a tropical rain forest today. Fog early on the 24th increasing thickness at 0900 GMT and dense at 0930 GMT. All was wet with the trees dripping moisture and the temperature in warm sector semi tropical air was 15.3C with 99% relative humidity. The species of trees and plants were not of the rain forest, but the effect was similar. High 1028 mb was off Cap Finisterre and a warm front over central England. Sunny in Thanet and Brighton. Pressure here falling on 1023 mb with a low 1019 mb lying to the south-west. It did clear up by the afternoon, with some glimpses of sunshine, planted out the hardened off runner beans on the vegetable plot (Chillingham Barns 25.7C Cardiff 22.3C, Santon Downham 5.2C, Portglenone 20.4 mm Mona 6.0 mm, Manston 11.8h Aberdaron 4.5h Valley 2.0h) [Max 18.7C Min 11.4C Grass 12.1C Soil at 5 cm 17.2C Rain 6.4 mm].

Much the same on the 25th grey skies, poor visibility and heavy rain at 0900 GMT about 14 mm/h. Pressure was on 1017 mb with low centred near Aberystwyth at noon tracking towards London reaching there at 1800 GMT. A cool overnight minimum of 9.9C, the weather didn't get any better with rain light to moderate at times through the day, maximum reaching 13.2C lowest of the month, and intermittent light rain in the evening before petering out. Rainfall duration was 11 hours (Wisley 23.1C Usk 17.5C, Dalwhinnie 6.9C, Winterbourne 32.4 mm Lake Vyrnwy 21.2 mm, Tiree 11.1h St Athan 1.7h Valley nil) [Max 13.2C Min 9.9C Grass 10.0C Soil 5 cm 15.1C Rain 17.5 mm]. On the morning of the 26th the ground was strewn with green sycamore leaves torn off the trees in the night by a strong NE'ly wind. Mostly cloudy with cumulus clouds decreasing. Visibility was excellent, very clear views of Llyn and Bardsey island. It was fine and dry, but feeling fresh. Outdoor Tumbler tomatoes have several small green tomatoes developed now they need a lot more sunshine (Heathrow 23.6C Usk 22.1C Capel Curig 16.7C Fair Isle 11.1C, Machrihanish 4.1C, Chillingham Barns 17.8 mm Cardiff 5.2 mm, Tiree 12.6h Aberdaron 10.3h) [Max 17.5C Min 9.8C Grass 8.0C Rain nil]. Keeping dry the the 27th began fine and sunny with good hazy visibility. Pressure was steady on 1019 mb with Atlantic-high 1029 mb W of Shannon. There were lows 991 mb Norwegian Sea and 1009 mb Bay of Biscay. It was breezy if not sheltered from the N'ly with a maximum temperature of 18.7C at 1450 GMT. Again there was rain in the S and SE of England the best weather and sunshine in the north. Late in the evening a large group of swallows were feeding over a nearby pasture field grazed by cattle and sheep (Porthmadog 23.4C Fair Isle 12.4C, Loch Glascarnoch 2.4C Bala 7.2C, Scilly 35.4 mm St Athan 1.4 mm, Valley 14.7h) [Max 18.7C Min 11.8C Grass 10.1C rain nil]. After a warm night minimum 13.3C the 28th began with broken clouds comprising cirrus, altocumulus and cumulus, and in moderate haze good visibility. Another dry day, fine and bright to begin then cloudier for a while with a maximum temperature of 19.4C. Low 1009 mb was over the Charente Maritime, France the Atlantic- high 1028 mb W of Shannon having a ridge to northern Britain. There was rain in places in southern Britain (Drumnadrochit 24.8C Porthmadog 22.9C, Tulloch Bridge 2.7C, Otterbourne WW 30.4 mm Mumbles Head 11.2 mm, Altnaharra 14.8h Valley 8.5h) [Max 19.4C Min 13.3C Grass 11.7C rain nil]. Fine, bright with a little weak sunshine early on the 29th with a cool NNE'ly breeze picking up at 0900 GMT. Pressure was on 1017 mb with a low 1011 mb Netherlands and frontal band over Wales and central England. Wet in S England, fine and sunny in Scotland. It was 60-y ago that the first nuclear powered space craft Transit IV-A was successfully deployed by the John Hopkins University. Using plutonium 238 as a fuel generating 2.7W the satellite confirmed that the Earth's equator was elliptical. Record heat in Canada with 49.6C recorded at Lytton. This village was burnt down the next days residents having 10 minutes to evacuate from the flames. Cooling centres were opened in Seattle and in succeeding days 130 fires were sparked in British Columbia by lightning strikes. The heat was caused by high pressure doming to the north and south. Heat spread eastward over the prairies to Saskatchewan where further grass fires were burning (Carlisle 25.3C Porthmadog 24.6C Fair Isle 11.3C, Tulloch Bridge 4.0C, St Catherine's Point 43.0 mm Hawarden 4.2 mm, Prestwick 15.0h Valley 9.7h) [Max 21.2C Min 11.7C Rain nil]. . The 30th began fine and bright, but before 0900 GMT cloud was thickening in a light SW'ly breeze becoming NE'ly at 0945 GMT. It remained mostly cloudy here, but was bright with sunny spells in Llandudno and Llanfairfechan. A warm sand humid day, a little sunshine towards the end of the afternoon before low cloud and fog encroached later in the evening (Cardiff 25.0C Fylingdales 11.6C, Shap 5.6C Sennybridge 7.5C, Manston 2.0 mm, Lerwick 14.6h St Athan 8.2C Valley nil) [Max 19.2C Min 10.7C Rain 0.3 mm].

A dry month with 44.9 mm of rainfall lowest since 2018. Warmer than average the monthly mean 14.7C (+0.5) & [+0.7] of averages equal highest since 1018 ranked 13 in station records since 1979. Despite 6 sunless days at RAF Valley it was a sunny month with 201.3h (96%) & [107%] of averages.



Home page Site map Top Home page Site map Top

July 2021

July 1 - began dull and slightly wet. At 0900 GMT the rain had stopped, but it was still dull and misty with poor visibility. Pressure was high 1022 mb between Iceland and Scotland and 1020 mb over Biscay, and low 1002 mb over the Baltic near Tallin. Despite the rain the soil surface remained dry and cracked. Britain remains north of the jetstream that is positioned over the Med. Did some strimming and planted a row of leeks (Strathallan 24.3C Usk 23.1C Aberdaron 13.2C, Braemar 2.6C, Weybourne 1.2 mm Rhyl 0.4 mm, Tulloch Bridge 14.7h Bala 6.4h) [Max 17.3C Min 11.9C Rain nil]. Pressure was steady on 1019 mb on the 2nd on a fine, close feeling, morning. The temperature was 12.8C with 98% RH. The weather was fair with cloud overhead, but clear sky to the south of the station. It was foggy in many places, but here visibility was good with the cloud clearing by afternoon when sunny and warm (Cambridge Niab 24.9C Hawarden 23.4C, Fair Isle 12.6C Aberdaron 17.4C, Braemar -0.1C, Drumalbin 12.4 mm, Manston 11.5h Aberdaron 9.7h) [Max 21.0C Min 11.9C Rain 1.8 mm]. After midnight on the 3rd there was light to moderate showery rain. In the morning it was mostly cloudy and feeling sticky. It was raining widely across Britain as pressure 1005 mb fell. Low 994 mb was over the Atlantic W of Shannon with a trough extended over Britain where it was showery. Our resident song thrush was singing, the pair nesting nearby must be having its second even third brood. They find plenty of snails in the garden and woodland, and hammer them on favourite stones to break them. Near midnight the tawny owls were vocal close to the house, but brown long-eared bats were out at dusk followed by the pipistrelles (45 kHz) a little later. There are plenty of insects and moths about, sometimes they softly pick moths off lighted window panes (Weybourne 23.8C Usk 22.0C Fair Isle 13.0C Aberdaron 16.1C, Redesdale Camp 8.1C, Waddington 27.4 mm Cardiff 12.4 mm, Stornoway 7.0h St Athan 0.9h Valley 0.6h) [Max 20.2C Min 14.4C Rain 10.6 mm]. Under low cloud on the slopes of the Snowdonia Mountains on the 4th visibility was good. At 0900 GMT with the temperature on 17.3C it felt sticky. There were heavy showers widely across Britain, not the July weather folk would like, but often typical rainfall averages in the 'summer monsoon' already on the up. The thrush was still singing. The temperature rose to 19.4C at 1234 GMT then declining through to 2125 GMT when it was 14.0C. We had one of those heavy showers at 1309 GMT, falling at a rate up to 48.8 mm/h 7.2 mm enough to make he gutters overflow (Leconfield 24.6C Hawarden 21.1C Wick 13.2C Libanus 16.6C, Ravensworth 9.2C, Plymouth 55.4 mm Mumbles Head 19.8 mm) [Max 20.2C Min 14.4C Rain 10.6 mm].

The herbaceous border in our Gadlys garden in July.

The morning of the 5th began with a fresher feel, fine and breezy with good misty visibility. Pressure was on 1003 mb , the UK was surrounded by a complex of depressions 999 mb at Malin Head at midnight. Showers continued in the north while there were sunny spells in the south we having the southern weather today. The Mars helicopter Ingenuity made its 9th successful flight of 2 mins 46 secs flying 625 m over challenging terrain after software update. The craft navigates itself and needs to correctly interpret the topography, each flight is more challenging this time taking pictures of scientifically interesting craters out of sight of the rover (Tibenham 22.2C Hawarden 20.0C Wick 13.7C Lake Vyrnwy 15.2C, Libanus 9.0C, Achnagart 34.0 mm Gogerddan 17.0 mm, Shoeburyness 8.4h) [Max 18.2C Min 12.3C Rain 5.8 mm].

A fine, but fresh feeling showery morning on the 6th with glimpses of sunshine. A 'could not make up it's mind day', we have been having several of these lately. Pressure 997 mb was rising, however, with a complex low 991 mb over the country filling and arriving off St Abbs Head 994 mb at 1800 GMT. The jet stream remains dipped on the southern side of the UK. A mostly cloudy afternoon with slight showers here, it was wet at Bodelwyddan (Rhyl) [28.8 mm] (Dunstaffnage 21.6C Hawarden 20.2C Spadeadam 13.0C, Katesbridge 4.0C, Alice Holt Lodge 27.8 mm Rhyl 27.2 mm, Tiree 14.4h Valley 3.6h) [Max 17.3C Min 13.4C Rain 0.3 mm]. After a mild night weather was fair on the morning of the 7th as pressure 1008 mb was rising. Low 999 mb was over the N North Sea with a ridge W of Ireland from Azores-high 1026 mb. Frontal cloud over Wales was slow to clear, but in what sunshine there was it felt somewhat warmer. Cloud thickened around noon and there was a heavy shower of rain falling at a rate of up to 34 mm/h at 1330 GMT. Later there was a little more sunshine, but it wasn't as warm (Linton on Ouse 23.6C Usk 21.5C Resallach 14.5C, Shap 4.4C, Dunkeswell 25.8 mm Swyddffynnon 6.3 mm, Dundrennan 13.3h St Athan 7.1h) [Max 18.3 Min 13.4C Rain 6.8 mm]. Pressure 1019 mb was still rising slowly on the 8th with a ridge to the west. Pressure was high 1023 mb Baltic and 1029 mb Azores. The best weather today was in central and eastern England, elsewhere very showery. Here a very dull with low cloud and mist, visibility was poor, turning quite dark under thick cloud from noon until about 16 GMT when it became brighter. The evening was sunny (Cardiff 24.1C Fair Isle 12.8C Aberporth 16.7C, Eskdalemuir 4.9C Sennybridge 8.2C, Tibenham 8.4 mm, Aberporth 11.4h Valley 4.7h) [Max 18.3C Min 12.2C Rain nil]. Early on the morning of the 9th it was fine and fairly bright, but before 0900 GMT cloud was thickening and here was drizzle and slight rain with visibility becoming poor. Pressure was high 1025 mb near Biarritz and 1025 mb over Russia with a weak ridge towards Britain. Here pressure was steady on 1021 mb and with a detached occlusion to the SW the day remained dismally dull (Wisley 24.9C Hawarden 21.8C Sennybridge 16.2C Kirkwall 13.3C, Sennybridge 7.0C, Balmoral 12.4 mm Porthmadog 1.4 mm, Leconfield 8.3h Hawarden 2.0h Valley 1.0h) [Max 17.2C Min 11.4C Rain 0.3 mm].

The 10th was equally not like summer beginning fine and becoming brighter the altocumulus declining , but cumulus clouds were building especially over the Snowdonia Mountains. It was nice with sunshine at Rhosneigr, but misty at Llandudno. A large toad greeted me as I entered the greenhouse this morning, we see them from time to time and in the garden. There was a disturbance over the south-west approaches, warmer at noon when the sun appeared briefly. Wet in SW England (Levens Hall 23.1C Hawarden 20.9C Aberporth 17.1C Fair Isle 14.5C, Altnaharra 8.5C Capel Curig 10.1C, Cardinham 44.4 mm Rhyl 6.0 mm, Aberdaron 12.4h Valley 3.8h) [Max 19.3C Min 12.5C Rain 0.1 mm]. A fine and dry morning on the 11th, mostly cloudy with the mountain summits just covered. Pressure was steady on 1014 mb with a low 1007 mb Shannon and a warm front over the Celtic Sea. It was raining on the far west parts of Cornwall and Pembrokeshire and sunny parts of E coast of England and East Anglia. Light to moderate rain reached here at 1327 GMT, a wet afternoon with little or no wind. Intermittent slight rain in the evening (Kinlochewe 22.7C Hawarden 22.4C Scolton 15.3C Cardinham 14.1C, Sennybridge 8.6C, Altnaharra 23.6 mm Milford haven 16.2 mm, Herstmonceux 5.6h Hawarden 1.0h Valley 0.5h) [Max 18.3C Min 12.1C Grass 7.7C Rain 7.4 mm]. At midnight on the 12th the low 1010 mb was near Cork, Ireland. It was foggy here and at 05 GMT soon thinning and the sun was breaking through by 0900 GMT visibility was good with cloud and fog still on the lower slopes of the mountains. That was the only brightness of the day as the cloud thickened again. A ridge of high-pressure was to the W, but with low 1008 mb over France weather remained disturbed. Mostly cloudy and dry here (Dunstaffnage 23.9C Tredegar 22.1C Aberporth 16.9C Loftus 15.5C, Dalwhinnie 7.7C, Topcliffe 55.0 mm St Athan 18.2 mm, Tiree 7.9h Aberdaron 3.6h Valley 0.9h) [Max 17.9C Min 13.7C Rain 0.1 mm]. Fog again overnight and at 0530 GMT thinning to mist at 0900 GMT on the 13th when visibility was good. Pressure 1018 mb was rising and in the sunshine it felt warmer. Farm spraying of cereals took place on the adjacent field to the NE when the wind speed at 10m was 10 mph. It had been lower earlier and later in the afternoon (Pershore 24.6C Usk 24.5C Aberporth 16.6C Lerwick 15.6C, Kinbrace 6.3C, Bramham 4.0 mm, Valley 12.0h) [Max 20.8C Min 12.2C Rain nil]. A cloudy morning on the 14th, with a temperature of 17.5C at 0900 GMT with good visibility. Cloud was hugging the tops of the Snowdonia Mountains, but began to break up with sunny spells developing. There were a few spots of light rain at 1330 GMT, not enough to wet the ground. Warm in the sunshine later in the afternoon and evening (Gosport 25.5C Cardiff 25.1C Aberporth 17.3C Fair Isle 15.5C, Balmoral 7.1C Sennybridge 8.2C, Morecambe 1.8 mm, Hawarden 14.0h Valley 9.9h) [Max 22.9C Min 12.1C Rain trace]. After a warm night with an air minimum of 14.6C another mostly cloudy start to the 15th low enough to cover the mountaintops with mist on the lower slopes. Here the visibility was good and there was a light NE'ly breeze. Pressure 1026 mb was rising with Atlantic high-pressure 1029 mb to the south-west. There was an occlusion over central England was associated with low 987 mb over the Norwegian Sea. Sunny in the afternoon, over 20 gannets joined a thermal over the weather station. We see them frequently passing over, likely transiting between Red Wharf Bay and Caernarfon Bay in both directions. Catastrophic flash flooding in Germany and parts of Belgium left more than 21 persons dead and extensive damage to property and infrastructure (Castlederg 25.7C Tredegar 25.2C Harris Quidnish 14.1C Aberporth 17.0C, Balmoral 7.8C Sennybridge 9.3C, Machrihanish 0.8 mm, Eskdalemuir 15.3h St Athan 14.6h) [Max 21.6C Min 14.6C Rain nil].

The first 15-days temperatures were close to averages the mean temperature 15.9C (+0.2) & [+0.1]. Rainfall of 34.4 mm was (39%) & [44%] of averages. It was duller than usual sunshine at RAF Valley had averaged 4.7 h per day with 12.0h on the 13th the only day having >10h.

The 16th was very fine, sunny and warm with a temperature of 18.6C at 0900 GMT. Pressure was on 1029 mb and it was a mostly sunny day (Coton-in-the-Elms 28.7C Usk 28.4C Aberporth 19.3C Fair Isle 15.6C, Santon Downham 6.4C Bala 7.5C, Stornoway 0.6 mm, Aberdaron 15.0h Valley 13.8h) [Max 23.7C Min 12.0C Rain nil].

The herbaceous border in our Gadlys garden in July.

There was not a cloud in the sky on the morning of the 17th and though milky visibility was very good. The only part of the UK that had a little cloud was the far N of Scotland, quite rare to see this clarity on the satellite images. There was moderate dew on the grass, but as it was fine and warm it soon began to dry as the NE'ly breeze picked up. The afternoon became hot with the temperature rising to 26.6C at 1439 GMT; the warmth continued into the evening only falling below 20C at 2000 GMT. Sidalcea growing in the herbaceous border Gadlys garden.The gannets were seen again in the afternoon, come to glide around on the Llansadwrn thermal (Ballywatticock 31.2C Usk 29.6C Aberporth 22.5C Lerwick 13.1C, Santon Downham 8.4C Bala 8.9C, Lerwick 2.4 mm, Morecambe 15.4h Aberdaron 15.0h) [Max 26.6C Min 14.3C Rain nil]. Another clear sky on the morning of the 18th and very warm it being 23.9C at 0900 GMT. There was a light breeze from the E and visibility was very good. Pressure was 1026 mb in the high 1029 mb over Shannon, Ireland. A hot day 27.5C, not one to be working in the sun in the garden, so kept to shady parts and enjoyed the flowering plants and butterflies. The number of bees were much less than usual which was of concern (Heathrow 31.6C Cardiff 30.2C Aberporth 25.5C Fair Isle 12.2C, Katesbridge 9.3C, Resallach 2.2 mm, Aberdaron 14.9h) [Max .27.5C Min 14.8C Rain nil]. Another hot day on the 19th beginning with two or three small cumulus clouds over mountains to the south of the station. Pressure steady on 1022 mb. The sky was again slightly milky and clear overhead all day with maximum solar radiation. Very fine and hot (Heathrow 31.4C Cardiff 30.9C Rhyl 25.0C Fair Isle 13.4C, Dalwhinnie 4.8C, Goudhurst 9.0 mm Usk 1.4 mm, Aberdaron 15.0h) [Max 25.3C Min 15.1C Rain nil].

A very fine morning on the 20th with a milky sky, but a line of small cumuli over mountains to the south. It was warm at 0900 GMT 22.8C dewpoint 18.5C. Fog were reported at Sennybridge (valley) and Valley (coastal) this soon burnt away. A sunny day and it has been a week without significant rainfall, irrigation of the vegetable plot and potted garden plants was necessary. A maximum of 25.9C at 1521 GMT, the THSW index generated by the AWS indicated a felt-like 33.9C in the sun (Heathrow 32.2C Usk 30.9C Aberporth 23.5C Baltasound 12.3C, Altnahinch Filters 6.9C Swyddffynnon 11.2C, Marham 43.8 mm, Almondsbury 14.4h Aberdaron 14.3h) [Max 25.9C Min 16.4C Rain nil]. Much the same on the 21st, no clouds with a milky sky and what was described as a 'heat haze'. Very fine, sunny and hot The temperature recorded at Castlederg 31.3C was the highest recorded in Northern Ireland. There were isolated thunderstorms through the day (Castlederg 31.3C Usk 30.8C Aberporth 23.3C Fair Isle 12.6C, Machrihanish 7.0C, Portglenone 2.4 mm, Valley 14.5h) [Max 27.2C Min 15.6C rain nil]. There were a few clouds on the 22nd, a band of cirrus encroaching from the SW and a few small cumuli over the Snowdonia Mountains. Starting off hot, 26.2C at 0900 GMT, phew! Mist and fog in parts of the NE while sunny in the S of Britain. Pressure was on 1023 mb with high 1026 mb over Scotland. With the sixth day of hot days with maximum of 25C or more, here 28.1C, moderate levels of ozone were recorded in Wales. The temperature at Armagh 31.4C stole yesterday's NI record. Isolated thunderstorms occurred during the evening including near Manchester and the Welsh Marches (Armagh 31.4C Gogerddan 31.2C Mumbles Head 26.0C Fair Isle 12.5C, Tulloch Bridge 5.4C, Sutton Bonington 6.0 mm, Eskdalemuir 14.1h Valley 13.7h) [Max 28.1C Min 16.3C Rain nil].AWS temperature record for the 7 days to the 23 July 2021. The 23rd began mostly cloudy with weak sunshine through cirrus and between cumulus clouds. It was warm 22.7C and 79% relative humidity at 0900 GMT. Visibility was moderate with a moderate haze developed. Overnight the air minimum temperature did not fall below 18.6C, a near record for the station; 18.9C was recorded in 2003. Today was the seventh consecutive hot day (>=25C) and that was a record; previously a spell of 6 consecutive days 19-24 July 1989 with a maximum of 28.0C this time 28.1C. The station record for the highest maximum is 34.9C recorded in 2006 during a Föhn wind off the Snowdonia Mountains. The increased heating here and globally is indicative of climate change, with increased storminess, heavy rainfall events leading to flash flooding, and more sunshine in places (Castlederg 30.1C Pembrey sands 28.7C Lake Vyrnwy 23.3C Fair Isle 13.4C, Altnaharra 7.3C Bala 12.2C, Isle of Portland 3.6 mm, Tiree 14.2h Valley 8.5h) [Max 25.9C Min 18.6C Rain nil]. A fresh morning on the 24th with the sky mostly covered with moderately high altostratus, altocumulus and cumulus clouds above the mountaintops of Snowdonia. There was a scattering of dried green sycamore leaves on the grass that was dry. The temperature was 16.3C at 0900 GMT, it felt fresh after the heat, but for a July of old 16.3C would be a reasonable maximum. It was breezy with an ENE'ly, kept mostly cloudy with a few sunny spells in the afternoon, no rain fell (Castlederg 27.6C Whitechurch (Pembs) 23.6C Libanus 17.6C Fair Isle 13.1C, Tulloch Bridge 8.2C, Boscombe Down 29.4 mm Cardiff 7.2 mm, Tiree 14.5h Valley 10.3h) [Max 20.4C, Min 14.8C, Rain nil]. There was broken cloud cover on the morning of the 25th high cirrus and cumulus clouds. Visibility was good, but hazy. Pressure was on 1010 mb with a complex depression 1005 mb over the Cherbourg Peninsular and Netherlands. The grass was very slightly damp this morning, likely guttation (exudation from the tips of the leaves) the minimum reading 11.6C. The 0900 temperature was 18.3C, a light ENE'ly again was picking up and there was this cool breeze off the sea through the day. The sky cleared in the afternoon and in the sunshine it was warm out of the wind the temperature rising to 22.1C. Hot again in Northern Ireland (Armagh 28.2C Usk 24.0C Aberporth 18.8C Aultbea 16.3C, Shap 4.2C Capel Curig 9.3C, St James Park 41.6 mm Cardiff 1.0 mm, Tiree 14.6h Valley 14.3h) [Max 22.1C 13.7C Grass 11.6C Rain nil].

Menai Suspension Bridge, Porthaethwy, Ynys Mon.

 

Pressure was on 1011 mb on the 26th with low 1006 mb over the North sea off Tayside while pressure was high 1016 mb N Italy and 1029 mb Azores. Sailing under the Menai Suspension Bridge.After a cooler night 12.2C it was very fine, sunny and warm with a scattered covering of cirrus and cumulus clouds. Sunniest in the north-west (Wellesbourne 27.3C Llysdinam 26.0C Ballypatrick Forest 14.7C Aberporth 19.2C, Shap 5.9C Bala 8.1C, Baltasound 9.8 mm, Dundrennan 11.1h Valley 11.0h) [Max 23.9C Min 12.2C rain nil]. The 27th began mostly cloudy with glimpses of weak sunshine Recently calm there was a light WSW'ly breeze, visibility was poor. There was complex low-pressure around Britain 1003-1006 mb, here it was 1011 mb. Thunderstorms developed early over the Irish Sea off Dublin and in Denbighshire. Cloud thickened and it went very dark at 1000 GMT the wind backing NE'ly. Thunder was heard here at 1140 GMT and continued getting close at 1203 GMT and very close at 1234-1237 GMT dying out by 13 GMT. Moderate to heavy rain up to 65 mm/h falling at 1159 GMT. The afternoon was brighter (Benson 24.8C Usk 22.9C Aberporth 17.8C Fair Isle 14.2C; Chillingham Barns 9.4C, Liscombe 35.2 mm Cardiff 12.2 mm, Boulmer 9.8h St Athan 7.0h) [Max 19.5C Min 14.1C Rain 18.9 mm]. A fine fresher morning on the 28th broken sky with altocumulus, towering cumulus with cumulonimbus clouds developing in the vicinity of the Snowdonia Mountains. Thunder was heard at 1012 GMT, 1305 GMT, and 2000 GMT. There was a heavy shower when the sky turned very dark at 1600 GMT, the temperature dropped 5C, and again in the evening. Recorded sferics were intense on the mountains during the afternoon around 14 GMT. Two women in a party of five were struck by lightning on Yr Wyddfa summit. They were rescued in dangerous conditions by the Llanberis Mountain Rescue Team and stretchered to Clogwyn Station where they were picked up by Coastguard Helicopter, based near Caernarfon, and taken to Ysbyty Gwynedd in Bangor. They were lucky to be alive (Holbeach 23.2C Hawarden 20.5C Lake Vyrnwy 15.9C Lerwick 13.0C, Banagher Caugh Hill 9.1C Libanus 9.8C, Aldergrove 50.0 mm Capel Curig 35.0 mm, Bournemouth 9.1h Aberdaron 8.8h) [Max 18.0C Min 12.3C Rain 2.6 mm]. The 29th began overcast and spotting with rain with a moderate SW'ly wind. Visibility was good, but the Snowdonia mountaintops were covered with cloud and mist. A Meto Yellow warning had been issued for parts of South Wales and SW England with an Amber for tomorrow naming the storm Evert arriving later. Pressure here was on 1008 mb with low 995 mb between Wick and Bergen (S Norwegian Sea of N North Sea?). It was mostly cloudy in the north with an occlusion over the Irish Sea. There was one sunny spell around 15 GMT when the temperature rose to 18.2C enjoyed by myself and several butterflies. Sunnier on the west coast with valley reporting 7.6h. The wind moderated quickly during late afternoon and becoming calm during the evening (Heathrow 23.3C Cardiff 20.9C Aberporth 16.9C Loch Glascarnoch 13.3C, South Newington 7.3C Libanus 8.9C, Altnahinch Filters 21.0 mm Milford Haven 6.4 mm, Shoeburyness 10.4h Aberdaron 9.3h) [Max 18.2C Min 11.5C Rain 6.6 mm]. Storm Evert was 992 mb on the 30th over the upper Severn estuary and Baltic low 991 mb at 0900 GMT. Pressure here was 1003 mb and we had a force 3 NE'ly. It was dull and wet with moderate to heavy rain overnight and turning light by morning with moderate misty visibility. It was to be a sunless day with light rain during the evening. There were at least 22 incidents involving crews and boats off Lands End and Scilly having to be rescued by RNLI and Coastguard helicopter during the night. Campers in Cornwall were hit by heavy rain and gales flattening some tents. Gusts of 62 mph were reported from Scilly St. Mary and 57 mph at St. Catherine's Point IoW. The winds were perhaps not as severe as had been forecast (gusts +70 mph), sailors and campers do not expect such winds that occurred at this time of year, but should have paid more attention to the forecasts. Two women were injured by a falling branch of an oak tree at Heveningham when the winds reach Suffolk (Weybourne 21.3C Usk 19.8C Lake Vyrnwy 14.5C Emley Moor 12.7C, Aboyne 9.0C, Cranwell 37.6 mm Scolton 26.6 mm, Camborne 4.8h Aberdaron 1.2h Valley 0.1h) [Max 15.9C Min 12.4C Rain 3.4 mm]. Overcast at first on the 31st, but brightening a little just before 0900 GMT. Cloud was low on the slopes of the Snowdonia Mountains. Pressure was on 1009 mb low 998 mb was over the E North sea and 994 mb S Norway, pressure remained high 1030 mb over the Azores. A disappointing day, the brightness disappeared and the day was mostly dull (Cavendish 23.1C Usk 20.4C Lake Vyrnwy 15.2C Ballypatrick Forest 13.1C, Wick 9.0C, High Mowthorpe 12.2 mm Swyddffynnon 4.2 mm, Camborne 9.8h Aberdaron 7.3h Valley 0.8h) [Max 17.1C Min 12.9C Rain 0.3 mm]

The month ended with a mean temperature 17.2C (+1.5) & [+1.4], highest since 2018 and ranking 7th in station records. Rainfall of 66.2 mm was (76%) & [85%] of averages driest since 2018 ranking 38th in Llansadwrn records since 1928. After a dull start it was a sunny month on Anglesey ranking 8th sunniest since 1931.

 



Home page Site map Top Home page Site map Top

August 2021

August 1 - began brightly after dawn with glimpses of sunshine before with cloud thickening the sky was overcast at 0900 GMT. The afternoon was brighter with sunny spells later. There was a slight shower in the evening; it was calm overnight. The beautiful bright pink flowers on self seeded plants of the Deptford pink Dianthus armeria have this year popped up in cracks between patio slabs (photos below left and right). We have conserved it in the garden for some years, this year it has been spectacular. An endangered species that has declined greatly in the past 50 years due to habitat destruction, it has been recorded on Anglesey in the past. It flowers from July to September and is usually found on disturbed ground along tracks, hedgerows and dry pastures (Ross-on-Wye 21.9C Cardiff 21.6C Aberporth 15.5C Loch Glascarnoch 12.1C, Achnagart 6.3C, Frittenden 25.8 mm St Athan 13.4 mm, Glasgow 9.9h Aberdaron/ Valley 9.2h) [Max 19.8C Min 10.9C Rain trace]. Deptford pink growing in our garden at Gadlys Llansadwrn, Anglesey.It was spotting with rain on the morning of the 2nd after a bright sunny start, but it was just a shower. The overnight air minimum was 10.3C, joint lowest of the month (with 28th). Pressure was on 1016 mb with highs 1020 mb Biarritz and 1032 mb Azores with a detached band of cloud over Ireland. Soon the cloud began to clear and we had a cool breeze off the sea, but in shelter it was pleasantly warm. It turned cloudier later in early evening (Hull 21.3C Usk 19.8C Aberporth 16.6C Fair Isle 11.9C, Katesbridge 1.8C Swyddffynnon 6.7C, Pershore 18.6 mm Libanus 10.6 mm, Morecambe 13.2h Valley/ Aberdaron 6.7h) [Max 17.1 Min 10.3C Rain trace]. Diantus armeria self seeded between slabs in our garden at Gadlys Llansadwrn, Anglesey.Fine sunny and warm on the 3rd, it had been calm overnight and a light SW'ly was picking up at 0900 GMT. We still had cold upper air from the north and a broken jetstream lay to the south, so continuing unsettled. Cloud encroached during the morning and the afternoon was cloudy with spits and spots of rain at times. Later in the afternoon the cloud cleared and it was a sunny end to the day (Heathrow 23.8C Cardiff 22.0C Aberporth 17.1C Lerwick 13.1C, Ravensworth 2.0C Sennybridge 3.6C, Helens Bay 17.2 mm, Leeming 13.8h Aberdaron 12.7h) [Max 18.5C Min 10.7C Rain trace]. The 4th began very fine and sunny with very good visibility, there were a few cumulus clouds over mountains to the south. Pressure on 1013 mb was falling slowly. A little cloud formed overhead during the middle of the day when breezy. Cloud clear later to give a sunny late afternoon and evening, but pressure 1009 mb continued to fall and the breeze backed SSE'ly. I spotted a painted lady butterfly on flowering majoram in the garden. To get a good photo with wings open I took several, they turned out interesting as different different angles were obtained when the shutter fired (Nantwich 24.0C Cardiff 23.5C Aberdaron 18.1C Fair Isle 14.7C, Shap 3.7C Sennybridge 5.0C, Killylane 20.4 mm, Morecambe 13.3h Aberdaron 12.7h) [Max 21.3C Min 11.0C Rain trace]. Painted-lady butterfly in our garden at Gadlys Llansadwrn, Anglesey.After a cool night it was a very fine morning on the 4th with a few cumulus clouds over the mountains to the south decreasing. . A little cloud bubbled up again around noon, then cleared with the afternoon sunny and warm 21.3C. Breezy (Nantwich 24.0C Cardiff 23.5C Aberdaron 18.1C Fair Isle 14.7C, Shap 3.7C Sennybridge 5.0C, Killylane 20.4 mm, Morecambe 13.3h Aberdaron 12.7h Valley 12.6h) [Max 21.3C Min 11.0C Rain trace]. The 5th began cloudy with slight showers, only a trace and the soil of the vegetable plot was looking rather dry again. There was rain before noon and this wetted the plot nicely with light to moderate rain in the afternoon the crops had perked up by evening. Rain ceased soon after 20 GMT. Sunless (Weybourne 23.9C Gogerddan 20.3C Lake Vyrnwy 14.5C Killylane 13.9C, Redesdale Camp 7.0C Llysdinam 9.7C, Porthmadog 30.2 mm, Tibenham 8.9h Hawarden 2.3h Valley 0.1h) [Max 18.1C Min 13.8C Rain 11.6 mm].

Dull with misty on the 6th intermittent slight rain and poor visibility through the day. Pressure 993 mb was rising with lows 990 mb at Malin Head and 988 mb Western Isles, hardly moving. Painted-lady butterfly (head on)in our garden at Gadlys Llansadwrn, Anglesey.Most places had active showery rain, sferics were seen to the S, E and N, showers in circulation around the low pressure. We were enveloped in more or less continuous slight rain and drizzle, heaviest at 10 GMT, the raingauge ticking over slowly through the day. It was clear on Llyn and hardly better on the west and north coasts of the Island (Heathrow 23.8C Cardiff 20.5C Lake Vyrnwy 15.4C, Libanus 12.6C Drumnadrochit 12.2C, Threave 40.6 mm Bala 16.6 mm, Manston 8.0h Aberporth 7.6h Valley 1.2h) [Max 17.8C Min 14.7C Rain 7.2 mm]. Painted-lady butterfly (wings open) in our garden at Gadlys Llansadwrn, Anglesey.Little change on the 7th with heavy rain (up to 80 mm/h) at first easing a little towards 0900 GMT. Pressure was steady on 991 mb the low 989 mb Malin head having an occlusion over North Wales and isle of man. Showers N, W and S, less so in Midlands and east Anglia. Spells of moderate to heavy rain through the day with brief appearances of the sun between (Hull 23.2C Rhyl 19.8C Libanus 15.3C Okehampton 13.1C, Llysdinam 11.0C Westonbirt 9.1C, St James Park 35.6 mm Llansadwrn 21.8 mm Porthmadog 18.6 mm, Weybourne 6.8h Aberdaron 1.6h Valley 0.1h) [Max 17.2C Min 13.5C Rain 21.6 mm]. A dull and wet morning on the 8th though not raining at 0900 GMT. Visibility was good under the cloud sheet with the mountaintops obscured above 1500 feet. Pressure 999 mb was rising with low 993 mb over the N Sea off Tayside filling, but slow moving, with an occlusion over North Wales. Painted-lady butterfly (underside)in our garden at Gadlys Llansadwrn, Anglesey.Mostly cloudy with occasional sunshine in the afternoon (Loftus 23.0C Valley 19.2C Lake Vyrnwy 14.9C Lough Fea 14.6C, Aviemore 9.7C, Spadeadam 66.8 mm Swyddffynnon 21.0 mm, Stornoway 13.9h Aberdaron 4.9h Valley 1.6h ) [Max 16.6C Min 14.1C rain 0.1 mm]. A bright morning on the 9th after a few spots of rain mainly cumulus clouds were broken and it was sunny. Pressure was steady on 1008 mb the low now 1001 mb mid North Sea/ Norwegian Sea between Shetland and Bergen. Pressure was high 1029 mb over the Azores and low 1015 mb over the Adriatic. The jetstream remains broken up. Mostly sunny in the afternoon, dug up some Arran Pilot potatoes from the vegetable plot very nice to have new potatoes ad freshly picked broad beans for dinner (Heathrow 23.0C Hawarden 21.4C Lake Vyrnwy 16.2C Lerwick 14.2C, Loch Glascarnoch 6.0C Mona 9.0C, Wiggonholt 41.2 mm Swyddffynnon 32.4 mm, Leeming 10.2h Valley 9.5h) [Max 19.0C Min 11.1C Rain 0.3 mm].

Some early rain had ceased and the morning of the 10th was overcast and misty. Visibility was moderate and at 0900 GMT it was spotting with rain again. It was raining along the western fringes and the north of Scotland. There were sunny spells in the E and SE. Briefly some brief sunshine and there was no more rain. Brighter with a little sunshine at times in the afternoon (Wellesbourne 25.3C Usk 23.4C Aberporth 17.7C Fair Isle 12.8C, Exeter 6.9C, Leuchars 22.8 mm Capel Curig 1.4 mm, Shoeburyness 13.4h St Athan 7.6h Valley 5.2h) [Max 19.8C Min 1.7C Rain 0.1 mm]. The 11th began very dull and dark with only 72W of sunlight at 0900 GMT. It was raining slightly and visibility was poor, it got a little lighter at 1020 GMT when it was 464W. The western fringes and central Scotland were again wet while it was sunny in the east and East Anglia. Pressure was 1014 mb and falling with a frontal wave 1001 mb S Iceland with triple point S Ireland. The Irish Sea was in moist warm sector air; a cold front lay over Ireland. Sicily recorded 48.8C today, the highest temperature ever recorded in Europe. There were many forest fires raging in Sicily and Calabria, as well as the recent fires in Turkey. The wildfires in North America in California and Canada continue with smoke blowing to eastern Atlantic shores. We were dampened down under dark skies by light to moderate rain in the afternoon the cold front reaching Anglesey at 18 GMT. Slurry was put on the adjacent field recently harvested during the day (Cavendish 25.8C Cardiff 22.3C Aberdaron 16.2C Baltasound 14.1C, Kinbrace 5.1C, Dunstaffnage 17.8 mm Whitechurch 8.4 mm, Shoeburyness 11.8h Aberporth 1.3h ) [Max 17.8C Min 13.7C Rain 3.3 mm]. The 12th began fine, bright and breeze with some glimpses of sunshine. Visibility was good with cloud on the mountaintops. The SSW'ly wind was force 5/6 increased to near gale force 7 in the afternoon. The tall trees especially spindly ash were waving about so it was dangerous to go into the wood today. It did not rain so the leaves did not get wet and branches heavy that would have been even more concerning. Pressure 1014 mb was falling with a low 988 mb lying to the NW off Malin Head. Picked some sweet peas. The supplied mixed seed this year contained mainly blue coloured flowers, and a fair amount of white, rather disappointing, but they have a good perfume. The weather had badly affected our outdoor tumbler tomatoes, the hot days followed by cold and wet has left them damaged, leaves and tomatoes that had started to ripen (Holbeach 24.7C Hawarden 21.9C Tredegar 17.1C Fair Isle 15.0C, Kinbrace 2.5C Swyddffynnon 6.3C, Machrihanish 12.2 mm Capel Curig 2.0 mm, Waddington 10.8h Hawarden 9.2h) [Max 18.4C Min 11.4C Rain nil]. After moderating overnight the wind was picking up again on the 13th with the SW'ly force 6. Pressure 1017 mb was rising with low 995 mb near Rockall and high 1026 mb SE Europe. It was windy NW Wales and W Scotland. Sunny, but very windy in the afternoon with it again unsafe in the woods (Coningsby 24.1C Hawarden 21.7C Lake Vyrnwy 16.4C Dalwhinnie 13.9C, Braemar 7.0C, Achnagart 43.6 mm Lake Vyrnwy 3.8 mm, Valley 10.9h) [Max 18.9C Min 13.4C Rain trace]. The 14th began mostly cloudy with spots of rain although the sun was breaking through at times around 0900 GMT. Pressure was on 1019 mb with a low 1002 mb W of Ireland and complex lows 988 mb Barents Sea. There was a low also off SW Ireland 1004 mb associated with low 1017 mb over the Azores unusual for this time of year. High pressure 1024 mb was over the Atlantic S of Greenland and 1025 mb over the Mediterranean. The jetstream remains broken. There was rain along the western fringe while farther east it was mostly sunny. The sky soon became overcast and there was slight rain or drizzle all day and into the night with a heavier spell at 21 GMT (Cavendish 25.6C Cardiff 24.0C Aberdaron 15.8C Fair Isle 15.0C, Katesbridge 6.9C, Achnagart 21.8 mm Valley 7.4 mm, Tiree 10.3h St Athan 4.7h) [Max 16.7C Min 13.7C Rain 3.8 mm Valley 8.4 mm]. The rain and drizzle overnight had not gone away on the morning of the 15th when it was wet with poor visibility. The disturbed synoptic chart is disturbed with pressure here 1011 mb with low 1008 mb SW Ireland and high 1029 mb to the west over the Atlantic. Pressure was also low 992 mb over the Gulf of Bothnia. Less windy today, the trees not looking so threatening just as well as the leaves were wet and heavy (Cavendish 26.4C Usk 20.3C Tredegar 16.7C Lerwick 12.1C, Port Ellen 5.6C, Baltasound 10.0 mm Scolton 7.6 mm, Manston 11.9h Aberdaron 2.8h) [Max 18.1C Min 13.9C Rain 3.8 mm].

The first 15-days temperatures were above the averages the mean temperature 16.4C (+1.0) & [+0.8] although the maxima were nothing of note, highest 21.3C on the 4th the only warm day. Rainfall of 48.4 mm was (50%) & [58%] of averages. Sunshine at RAF Valley averaged 5.2 h per day.

The 16th began dull with low cloud and moderate visibility. At 0900 GMT the cloud overhead looked to be thinning, but it was short lived and soon returned to 8/8 and was thick enough at times with the NW'ly Atlantic airflow for the odd spot or two of rain. With pressure high 1030 mb S of Iceland pressure here 1019 mb was rising with lows 999 mb Baltic, 1010 mb Adriatic and 1016 mb Azores on the strange looking synoptic chart. The old cricket field with a crop of cereals was sprayed late afternoon (Strathallan 21.8C Cardiff 20.4C Capel Curig 14.1C Altnahinch Filters 13.0C, Kinbrace 4.9C, Fyvie Castle 5.8 mm Aberdaron 0.6 mm, Kirkwall 10.8h St Athan 2.7h ) [Max 15.9C Min 11.5C Grass 9.4C Rain 0.4 mm]. Another overcast and dull day on the 17th, low cloud mist, poor visibility and slight rain and/ or drizzle throughout. The light level just 53W at 0900 GMT rising to 178 W the maximum at 0952 GMT. The temperature was 13.3C with 98% relative humidity. Pressure steady on 1021 mb with high 1031 over sea area FitzRoy. We had moist warm sector air over the Irish Sea, pressure was low 997 mb over the Baltic. Very dark day under thick cloud with drizzle at times, sunless (Strathallan 23.9C Usk 20.9C Libanus 15.0C Altnahinch 13.6C, Baltasound 7.1C, Altnahinch 10.0 mm Trawsgoed 6.6 mm, Glasgow 8.2h St Athan 2.4h) [Max 16.1C Min 12.5C Rain 0.9 mm]. Fungi on rotting timber in the wood at Gadlys Llansadwrn, Anglesey.Yet another dismal summer day on the 18th beginning overcast with intermittent drizzle and poor visibility. Pressure was on 1019 mb with slow moving low 987 mb Baltic dominating the weather against a ridge of high pressure in a curve from SE Greenland 1023 mb via the Celtic Sea to the Azores 1026 mb. At a summit weather station on Greenland along with abnormal high temperatures it rained for the first time on record. It was drier in one or two places around the coast of Anglesey including Rhoscolyn and Rhosneigr, here near the mountains drizzle at times and sunless with very little wind everything wet (Bridlington 24.8C Usk 21.3C Whitechurch 14.9C Resallach 13.1C, Balmoral 7.5C Lake Vyrnwy 9.6C, Altnahinch 6.4 mm, Swyddffynnon 5.0 mm, Boulmer 10.9h St Athan 1.5h) [Max 15.2C Min 12.4C Rain 1.8 mm]. Again the 19th day beginning overcast with heavy drizzle and in the mist very poor visibility. Not a great volume of rain 0.2 mm measured. With pressure steady on 1012 mb there was low-pressure 1010 mb over Shannon that had an occluded front over the Irish Sea. Rain was reported widely, but cleared up somewhat in the afternoon when there was a glimpse of sunshine (Wellesbourne 23.6 C Hawarden 22.2C Aberdaron 16.7C Fair Isle 13.4C, Redesdale 4.5C Libanus 6.8C, Boscombe Down 12.2 mm Swyddffynnon 4.6 mm, Shoeburyness 6.3h Aberporth 1.7h) [Max 19.2C Min 16.0C Rain 0.2 mm].

The 20th had a more promising start being brighter with a little weak sunshine and it felt a little warmer at 17.4C. The low W of Shannon had deepened 997 mb arriving off Malin head at 0900 GMT with pressure here little change at 1013 mb. Pressure was high 1018 mb NE France and Belgium. The early promise was slow to develop the morning remaining dull, but improved a little in the afternoon with a glimpse of sunshine. Rain showers in the evening and rain after midnight (Cavendish 23.8C Hawarden 21.8C Lake Vyrnwy 17.5C Lerwick 12.5C, Tyndrum 6.7C Hawarden 12.8C, Derrylin Cornahoule 10.0 mm Aberporth 2.4 mm, Shoeburyness 8.7h Hawarden 3.6h) Max 20.3C Min 13.9C Rain 12.0 mm]. Light rain after midnight turned heavy at 0507 GMT falling at a rate of up to 14 mm/h. By the morning of the 21st 12.0 mm had fallen, the second largest in the month. Light rain continued for a while then stopped. Pressure was on 1014 mb with a frontal wave 1006 mb over the Irish Sea associated with low 989 mb Greenland. A dull and damp day, sunless (Yeovilton 22.7C Cardiff 20.9C Lake Vyrnwy 16.2C Fair Isle 13.1C, Baltasound 4.0C, Eskdalemuir 39.6 mm Gogerddan 29.0 mm, Camborne 5.7h Aberporth 1.2h) [Max 17.8C Min 14.5C Rain 1.9 mm]. The 22nd began overcast and dull with moderate misty visibility. With little wins currently calm at 0900 GMT all surfaces were wet. Low 1013 mb was off the Western Isles, but pressure 1020 mb was rising rapidly the result of a ridge of high-pressure to the Celtic Sea from Atlantic-high 1025 mb off Cap Finisterre. The morning remained cloudy, but the afternoon brightened up with some sunshine coming along (Bournemouth 24.6C Usk 23.8C Aberporth 17.1C Lerwick 13.3C, Aviemore 9.3C Bala 10.5C, Leek 22.4 mm Trawsgoed 12.0 mm, Tiree 11.3h St Athan 8.5h Valley 4.2h) [Max 20.6C Min 13.5C Rain nil]. The 23rd also began mostly cloudy 5 oktas cover at 0900 GMT with a few cumulus clouds building in the vicinity. Pressure was on 1030 mb and convective development was limited and the afternoon was fine and sunny. We had the electricity supply off from 0730 GMT to about 15 GMT as work was being done on renewing cables and wooden poles nearby (Castlederg 24.3C Hawarden 22.5C Libanus 18.0C Fair Isle 14.3C, Altnaharra 6.1C Sennybridge 6.3C, Pennerley 0.8 mm, Tiree 12.3h Aberporth 9.9h Valley 9.3h) [Max 21.9C Min 12.2C Rain nil]. Visibility was very good and clear on the morning of the 23rd under 5 oktas of cloud, mainly altocumulus and cirrus with some cumuli bubbling up over the Snowdonia Mountains. The afternoon was mainly sunny with the temperature rising to 21.9C the highest of the month (Castlederg 24.3C Hawarden 22.5C Libanus 18.0C Fair Isle 14.3C, Altnaharra 6.1C Sennybridge 6.3C, Pennerley 0.8 mm, Tiree 12.3h Aberporth 9.9h Valley 9.3h) [Max 21.9C Min 12.2C Rain nil]. With pressure high and steady on 1032 mb on the 24th within UK high 1033 mb centred on the Tay estuary it was a very fine sunny day. Sunniest again in the north-west (Strathallan 26.3C Cardiff 23.2C Lake Vyrnwy 15.5C Fair Isle 14.2C, Kinbrace 5.3C Bala 8.2C, Houghton Hall 0.6 mm, Tiree 13.3h Aberdaron 11.9h Valley 11.0h) [Max 20.5C Min 12.3C Rain nil].

On the 25th fog developed after midnight that began to clear after 07 GMT, the morning was rather misty with poor visibility under the stratocumulus/ fog. Pressure was on 1029 mb with high 1032 mb Rockall. There was a cold front over the Norwegian Sea associated with low 997 mb over the Baltic that was affecting north-eastern coastal areas, but here the cloud lifted the morning brightening and it turned out to be a warm sunny afternoon (Tyndrum 27.2C Valley 21.6C Mona 20.6C Libanus 16.4C Fair Isle 13.9C, Shap 6.2C Trawsgoed 7.5C, Weybourne 1.4 mm, Prestwick 12.5h Aberdaron 9.4h Valley 8.3h) [Max 20.9C Min 12.8C Rain nil]. Overnight cloud had encroached and on the morning of the 26th the sky was mostly cloudy. Visibility was moderate in haze and it was calm. The temperature was 17.2C at 0900 GMT. With little rain the undisturbed met plot soil surface was once again nearly dry. Pressure was high 1030 mb N of Scotland and Norwegian Sea and a cold front was lying from the Western Isles to Thanet. Pressure here was 1025 mb in an Omega Block between low 990 mb SE Greenland and low 1000 over the Baltic. The sky cleared around 14 GMT the rest of the afternoon turning sunny and warm. Buzzards were flying through the wood several times today possibly searching for prey (Tyndrum 25.2C Cardiff 24.3C Aberporth 17.3C Fair Isle 13.3C, Swyddffynnon 6.6C, Houghton Hall 1.6 mm, Tiree 12.8h Aberdaron 10.0h) [Max 21.4C Min 12.6C Rain nil]. Clear sky continued overnight so it was a little cooler with an air minimum of 10.8 C and it fell to 7.3C on the grass, lowest of the month, with heavy dew formed. Pressure 1026 mb was rising on the 27th with a few small cumuli over the mountains E of Conwy and S towards Llyn. The cold front was lying from the Celtic Sea over the bay of Biscay to Biarritz. After 5 warm days each >20C today was cooler, but no less sunny (Kinlochewe 24.2C Porthmadog 22.1 C Libanus 15.6C Fair Isle 13.0C, Braemar 1.3C Sennybridge 2.7C, Fylingdales 1.2 mm, Stornoway 12.8h Aberdaron 12.5h) [Max 17.8C Min 10.8C Grass 7.3C Rain nil]. After a cooler night the 28th was very fine feeling warm with pressure steady on 1029 mb within the high stationed over NW British Isles rising to 1031 mb at noon. The air minimum of 10.3C was jointly with the 2nd lowest of the month. A sunny day. The cereal crop in the old cricket field at Gadlys adjacent to the weather station was combined today, by late afternoon all was finished and the straw gathered into big bails (Strathallan 24.4C Usk 22.0C Aberporth 17.5C Fair Isle 14.2C, Shap 1.9C Capel Curig 4.4C, Brooms Barn 1.4 mm, Morecambe 12.5h Valley 12.3h) [Max 19.6C Min 10.3C Rain tr]. The 29th began overcast with drizzle showers either side of 0900 GMT and moderate visibility. Pressure continued high on 1028 mb with high 1032 mb to the NW off W Scotland. By 0920 GMT the cloud and mist lifted with sunny spells and clear sunshine in the afternoon after 1300 GMT (Plymouth 24.1C Pembrey Sands 23.0C Aberporth 17.7C Fair Isle 12.6C, Shap 4.8C Sennybridge 4.9C, Fyvie Castle 1.2 mm, Camborne 12.6h Lake Vyrnwy 9.0h Valley 3.3h) [Max 20.4C Min 11.2C Rain tr]. It was raining in the NE of England this morning of the 30th, but not here. It was fine with a somewhat cool E'ly breeze. Visibility was very good with blue sky to the S of the station. Pressure 1029 mb was rising with high 1034 mb off NW Scotland. The sky cleared by afternoon when it was sunny, Sunniest and warmest in the north-west (Castlederg 21.3C Gogerddan 18.8C Libanus 13.2C, Whitechurch 6.0C, Durham 2.4 mm, Tiree 7.7h Valley 6.1h) [Max 18.4C Min 12.8C Grass 9.5C Rain tr]. The 31st began with some drizzle and overcast with altostratus cloud clear of the western Snowdonia mountaintops, but touching the eastern summits. At 0900 GMT visibility was very good and clear. High pressure 1038 mb was off the W of Scotland and was rising here here 1033 mb. A fine, but dull day and sunless day, the maximum 15.4C second lowest of the month (Tyndrum 20.2C St Athan 18.2C Lake Vyrnwy 13.2C Pennerley 12.9C, Braemar 0.3C Lake Vyrnwy 9.9C, Fylingdales 4.2 mm, Tiree 11.2h Lake Vyrnwy 0.6h) [Max 15.4C Min 12.8C Rain tr].

The month ended with a mean temperature 15.6C (+1.2) & [0.0], lowest since 2017 and ranking 13th warmest in station records since 1979. Rainfall of 69.0 mm was (66%) & [77%] of averages driest since 2018 ranking 27th in Llansadwrn records since 1928.

 



Home page Site map Top Home page Site map Top

September 2021

September 1 - was overcast and dull with a cool E'ly breeze and good slightly hazy visibility. Pressure was on 1035 mb with high 1039 mb between NW Scotland and Iceland. The day kept dry and dusty here with some rain in places in the east (Tyndrum 24.6C Hawarden 17.9C Lake Vyrnwy 14.1C Kirkwall 13.4C, Braemar 2.2C Bala 7.5C, Durham 1.0 mm, Tiree 13.1h Abedaron 2.2h) [Max 15.7C Min 10.5C Rain nil].

The big slack (left of panorama) at Aberffraw dunes, Ynys Mon.

A fine, but dull morning on the 2nd under overcast sky with moderate to good hazy visibility. Pressure was high on 1032 mb within high 1035 mb off the Western Isles. Lady's-tresses orchid growing on dune slacks at Aberffraw dunes, Anglesey.Brightening through the morning with sky slow to clear even in the afternoon. At Aberffraw exquisite Lady's-tresses orchids no more than 5 cm or so tall were in flower in places including the big slack, autumn gentian and marsh helleborines still in flower. Autumn gential (Felwort) growing on dune slacks at Aberffraw dunes, Anglesey.An area at the inland (east end) had been cleared of top sand to one side of the path the spoil heaped on the other. The reason for this is obscure, possibly an experiment to observed recolonisation (Braemar 21.8C Porthmadog 20.8C Lake Vyrnwy 14.5C Wick 12.5C, Lake Vyrnwy 14.5C Katesbridge 3.4C, Frittenden 0.2 mm, Morecambe 8.2h Aberdaron 5.4h Valley 4.2h) [Max 18.2C Min 11.4C Rain nil]. Fine, but quite dull on the morning of the 3rd the overcast sky remaining all day. Overnight the grass minimum had been 6.7C the lowest since 23 June 5.0C. It was dry so that autumn jobs could be done in the garden trimming back hedges. I found several ripe plums which were nice to eat. Pressure was steady on 1025 mb the high being centred near Bettyhill on the N Scottish coast. Pressure was low 1016 mb over the Bay of Biscay (Gosport 24.3C Usk 21.4C Lake Vyrnwy 14.1C Inverbervie 12.0C, Mona 8.4C Katesbridge 4.2C, Baltasound 2.2 mm, Manston 8.8h St Athan 3.9h) [Max 16.4C Min 10.5C Grass 6.7C Rain nil]. Carline thistle on Aberffraw dunes, Anglesey.The high pressure had transferred NE to S Norway on the 4th and was 1026 mb. Pressure here was 1019 mb and there was a patch cloud over North Wales, but at 0900 GMT it was looking brighter with a little blue sky appearing. Visibility was moderate to good with haze. We had unpleasant heavy dust drifting across on a 4-6 mph NE'ly breeze all afternoon the result of persistent heavy rolling of the ploughed field adjacent to the weather station (Bude 24.1C Gogerddan 23.4C Lake Vyrnwy 17.7C Dalwhinnie 13.5C, Whitechurch 8.5c Kinbrace 2.7C, Leuchars 5.6 mm, St Athan 10.1h) [Max 20.6C Min 12.7C Rain nil].

A very fine and bright morning on the 5th with weak sunshine trough 6 oktas of altocumulus and altostratus clouds. Pressure 1021 mb was rising with high pressure 1028 mb over the Baltic. A low 1005 mb over the Atlantic off Cap Finisterre was moving NE over the Celtic Sea and there was a shower trough off Malin head that did not affect North Wales. A dry day, sea breezes light and intermittent and turning sunny and warm in the afternoon. Dug up the last of the pink fir apple potatoes very good this year (Wiggonholt 27.1C Trawsgoed 25.3C Milford Haven 19.6C Resallach 15.0C, Loch Glascarnoch 4.7C Bala 5.4C, Giants Causeway 15.0 mm, Manston 11.4 Aberdaron 9.4h Valley 4.9h) [Max 23.7C Min 12.2C Grass 8.7C Rain nil]. Carline thistle from above on Aberffraw dunes, Anglesey.The 6th began disappointingly dull with poor misty visibility, but it was dry. Pressure was high 1029 mb over E Europe frontal cloud affected Scotland, N England and N Ireland. Pressure here was on 1023 mb. Ozone levels were moderately high the first time for a while. The morning remained overcast the visibility slowly improving and by afternoon cloud burnt away and it turned sunny and warm again (Larkhill 28.9C Cardiff 27.2C Aberdaron 18.8C Lerwick 15.7C, Loch Glascarnoch 8.2C, Altnahinch 7.0 mm, Camborne 11.9h Lake Vyrnwy 8.8h Valley 3.7h) [Max 22.0C Min 14.5C Rain nil]. A cloudless sky on the morning of the 7th with good visibility, but moderately hazy. Very fine, sunny and warm in a plume of air from the south the temperature at 0900 GMT 18.1C. Pressure was on 1021 mb with a high 1031 mb over the Black Sea. There was a thundery low 1007 mb off Cap Finisterre. A hot afternoon in parts of Wales 30.7C at Gogerddan and 26.9C at Valley (Gogerddan 30.7C Llansadwrn/ Mumbles Head 25.2C Lerwick 16.3C, Shap 7.1C Capel Curig 7.9C, Harris Quidnish 3.4 mm, Almondsbury 12.1h Aberdaron/ Valley 12.0h) [Max 25.2C Min 13.8C Rain nil]. At Aberporth overnight air minimum was 20.5C the warmest September night on record in Wales since 1949 in Rhyl. Grass-of-Parnassus growing on Aberffraw dunes, Anglesey.The 8th began with temperatures similar to the S of France, at 0900 GMT here it was 21.3C. There was broken cloud cover of altocumulus and lenticular altocumulus and good hazy visibility. It was a hot day the temperature rising to 28.2C highest in September on record at the station, previous highest 28.0C on 4th 2005, and 28.3C at Gorwel Heights, Gorddinog AWS reported 29.3C and Valley 29.4C. Thunderstorms developed just before 2157 GMT with thunder and lightning seen towards Caernarfon then moving along the Menai Strait over Anglesey to Penmon ending 2325 GMT. The maximum number of strikes were at 2245 GMT and rain fell here at a rate of up to 98 mm/h beginning at 2220 GMT ending at 2300 GMT amounting to 10.6 mm (Northolt 30.3C Hawarden 29.5C Milford Haven 19.0C Fair Isle 16.8C, Braemar 7.9C, Bala 9.7C, Plymouth 33.4 mm Milford Haven 3.8 mm, Weybourne 12.1h Hawarden 9.2h) [Max 28.2C Min 18.0C Rain 15.8 mm]. Rain continued after midnight on the 9th ceased about 0230 GMT and accumulated 15.8 mm by 0900 GMT. It was then fine and felt warm and humid, visibility was poor. Pressure was steady on 1006 mb with thundery low 1004 mb Shannon. Pressure was high 1025 mb Black Sea and there was a ridge from Azores high 1018 mb over the Atlantic W of Ireland. Brightening later with some sunny spells, showery N and S of here in the morning. Heavy shower up to 40 mm/h fell at 1842 GMT (Santon Downham 26.6C Hawarden 24.6C Sennybridge 19.3C Lerwick 12.4C, Tredegar 14.4C Redesdale 10.0C, Banagher Caugh Hill 39.8 mm Gogerddan 37.6 mm, Manston 8.8h Valley 3.6h) [Max 22.4C Min 16.2C Rain 5.5 mm].

Further showers came along after midnight on the 10th bringing the rainfall up to 5.5 mm by 0900 GMT. A fine morning with a brightening sky though visibility was moderate with mist and the cloudbase was low on the mountains in the west. Pressure 1008 mm was rising with low 1005 mb Malin Head tracking towards Scotland. There was an occluded frontal system over N Wales and the jet stream remains broken. Rain fell widely across the UK today, wet in Scotland and Snowdonia, here cloudy at noon with slight showers with just glimpses of sunshine morning and later in afternoon (Cranwell 25.0C Hawarden 22.1C Tredegar 17.1C Baltasound 13.5C, Ravensworth 11.3C, Glasgow 22.8 mm Capel Curig 15.0 mm, Manston 3.9h Lake Vyrnwy 1.9h Valley 0.4h) [Max 20.2C Min 15.7C Rain 0.3 mm]. An overcast morning on the 11th with moderate misty visibility after recent slight rain. Pressure 1016 mb was rising with low 1006 mb over the junction of the Norwegian and North Seas. Pressure was high 1021 mb S Spain. Hurricane Larry was near Nova Scotia. Dry with some brightness and a little sunshine in the afternoon, again another rain day in much of the country (Cavendish 24.6C Usk 21.1C Capel Curig 16.2C Lerwick 11.9C, Exeter 9.9C, Stornoway 34.2 mm Porthmadog 4.2 mm, Camborne 9.6h St Athan 6.2h Valley 1.8h) [Max 17.9C Min 14.6C Rain trace]. Much the same on the 12th pressure was still rising with lows 1004 mb S Norwegian Sea and 1006 mb over the Atlantic off Iberia. Overcast here with stratus cumulus cloud low on the Snowdonia Mountains and there were spots of rain at times throughout the day with glimpses of sunshine especially later in the afternoon (Cavendish 23.2C Usk 20.2C Capel Curig 14.6C Balmoral 12.2C, Libanus 6.1C, Whitechurch 10.0 mm, Manston 8.6h St Athan 2.4h) [Max 16.3C Min 13.9C Rain 0.2 mm].

Stand of Goat's-beard at Tywyn Aberffraw, Ynys Mon.

The band of cloud, a trailing warm front associated with Atlantic-low 1004 mb off Iberia, had moved overnight and the morning of the 13th was overcast. It was calm and raining slightly with pressure steady on 1017 mb and the temperature 15.2C with 95% RH. Much the same through the day, slight rain and four brighter periods when the rain stopped, but the day was sunless. Light rain during the evening (Santon Downham 21.9C Llansadwrn 20.2C Lake Vyrnwy 14.5C Spadeadam 12.6C, Redesdale 1.7C, Milford Haven 13.8 mm, Kirkwall 8.4h Valley nil) [Max 16.8C Min 12.8C Rain 8.0 mm]. Light rain turned heavy (12 mm/h) at 0017 GMT then light to moderate at times ceasing on the 14th about 06 GMT. Stand of goats-beards or meadow salsify growing on Aberffraw dunes, Anglesey.The sky was clearing and was to 5 oktas at 0900 GMT. Pressure was steady on 1013 mb with frontal cloud over Ireland and the west of Britain moving off. It was calm, visibility after the rain was very good, almost clear. Becoming fine and bright with the afternoon sunny. The rain band moved eastward and was heavy over East Anglia later (Gosport 23.8C Portmadog 21.3C Lake Vyrnwy 16.9C Pateley Bridge 12.7C , Kinbrace 6.8C, Cambridge Niab 51.6 mm Valley 9.0 mm, Aberporth 10.6h Valley 6.1h) [Max 20.2C Min 13.7C Rain trace dew]. With mostly clear sky overnight the morning of the 15th was fine and sunny. There was heavy dew on the grass the minimum thermometer reading 7.8C. A little cloud, cirrus and some cumuli were beginning to form. Visibility was good with some mist lingering in low-lying places. A sunny afternoon weeded and forked over part of the vegetable plot ready to receive plantings of winter brassicas (Usk 23.1C Aberporth 17.6C Fair isle 13.3C, Shap 2.3C Capel Curig 5.0C, Durham 11.0 mm Cardiff 0.6 mm, Morecambe 10.6h Lake Vyrnwy 7.8h Valley 5.4h) [Max 21.4C Min 11.0 Rain 2.2 mm].

The first 15-days temperatures were well above the averages the mean temperature 16.9C (+3.2) & [+2.9] with the highest maximum 28.2C on the 8th (+5.6). It had been drier than usual with rainfall of 32.0 mm (31%) & [32%] ] of averages. Sunshine at RAF Valley averaged 3.5 h per day.

A fine bright morning on the 16th with lingering mist visibility was poor. Soon burning off in the developing sunshine, cumulus clouds were bubbling up over the mountains. Visibility improved in the afternoon with fine views across to Llyn and Bardsey Island from Aberffraw Bay (Shoeburyness 23.7C Cardiff 22.3C Aberdaron 17.5C Fair Isle 13.7C, Libanus 9.0C Katesbridge 4.2C, Kinbrace 6.6 mm, Shoeburyness 10.4h Aberdaron 8.8h Valley 8.0h) [Max 19.4C Min 13.3C Rain nil].

View of Aberffraw bay from the dunes, Ynys Mon.

Another bright and fine morning on the 17th with good visibility; cumulus clouds were increasing from the almost clear sky at dawn. Pressure was steady on 1011 mb with low 990 mb Iceland with a trough to S Ireland. There was a S'ly breeze and the day remained mostly fine here with a few spots of rain at times in the afternoon. Rain on a cold front sliding north was falling on Ireland and western part of the Irish Sea, showers Cornwall and and NW Scotland (Blackpool 22.3C Hawarden 21.4C Scolton 16.6C Fair Isle 14.2C, South Newington 6.0C Usk 8.4C, Killylane 15.8 mm Whitechurch 2.2 mm, Leeming 8.4h Hawarden 6.0h Valley 1.9h) [Max 20.1C Min 13.9C Rain tr]. Burnet rose growing on Aberffraw dunes, Anglesey.Warm frontal cloud (1011 mb) had encroached overnight and was lying from Brest over Wales with pressure here 1014 mb. The temperature at 0900 GMT on the 18th 15.2C (dewpoint 14.9C) RH 98%. The grass was wet with guttation and the day remained damp and sunless, it was sunny further east. We had light to moderate rain from 19 GMT that turned heavy for a while at 2020 GMT (8.8 mm/h) (Northolt 25.3C Usk 23.3C Aberporth 16.7C Fair Isle 13.3C, Braemar 3.2C Mona 9.9C, Porthmadog 12.8 mm, Leuchars 9.9h Hawarden 2.6h) [Max 17.8C Min 13.2C Rain 8.4 mm]. On the morning of the 19th rain at 0900 GMT was easing after recent showery rain. Pressure 1014 mb was rising with an occlusion over the Irish Sea associated with low 990 mb N Iceland. The cold front was lying to the E along the spine of the UK. The sky began clearing at 0950 GMT and it was a day of clouds and sunny spells (Cavendish 22.6C Cardiff 21.0C Aberporth 15.7C Fair Isle 13.6C, Katesbridge 7.7C Libanus 8.0C, Andrewsfield 41.2 mm Bala 8.6 mm, Aberdaron 9.1h Valley 7.3h) [Max 18.8C Min 11.6C Rain 0.2 mm]. It was cooler overnight under mostly clear sky with the harvest moon shinning brightly. On the morning of the 20th there was heavy dew and the grass minimum thermometer read 5.8C, the lowest since 23 June (5.0C). A very fine, sunny and dry day (Cardiff 22.4C Aberporth 16.5C Fair Isle 13.8C, Braemar 0.2C Swyddffynnon 3.9C, Weybourne 23.2 mm, Almondsbury 11.4h St Athan 10.4h Valley 8.7h) [Max 19.6C Min 10.3C Grass 5.8C Rain nil]. The turning point in the astrometric seasons on the 21st the autumn solstice from now onwards the nights will become longer, but as the weather remains kind I won't think about that. A fine morning with good slightly misty visibility, the sky mostly cloudy with moderately high altostratus with bands of cumulus at lower level near the Snowdonia Mountains. Pressure was steady on 1032 mb, Atlantic-high 1033 mb off Cap Finisterre had a ridge towards southern Britain. Atlantic-low 972 SW Iceland was deepening and reached Scotland at noon 961 mb. Grass was still growing at the weather station although the total yield this season 71 kg per hectare is one of the lowest on record due to the cold wet spring. Soil moisture under grass was 39.8% dry mass while on the bare met plot it was 27.1% dry mass, well below the saturated water percentage of 70%. Following recent rain the top 2 cm of grass stubble, roots and soil was 81.5% dry mass. The recently direct drilled and traditional ploughed and seeded fields adjacent to the station had germinated and were looking green (Fyvie Castle 23.5C Cardiff 21.5C Valley 17.5C Fair Isle 14.7C, Shap 4.6C Sennybridge 4.9C, Achnagart 0.8 mm, Camborne 10.2h Aberdaron 9.1h Valley 4.9h) [Max 18.8C Min 12.1C Grass 7.3C Rain 0.2 mm]. It was fine and sunny in East Anglia and SE England on the morning of the 22nd, but here it was overcast with drizzle and moderate to poor visibility. Pressure was 1028 mb within a high 1032 mb W FitzRoy to Belgium. Deep was low 951 mb was over the Norwegian Sea with a cold front over Scotland. The morning soon brightened, the drizzle stopped and sunshine broke through giving a sunny afternoon with the temperature 13.3C. Several speckled wood butterflies were about in the dappled shade of the woodland edge. Planted out a row of late purple sprouting broccoli (Heathrow 23.0C Usk 21.0C Sennybridge 15.4C Loch Glascarnoch 12.9C, South Newington 4.8C Sennybridge 6.1C, Achnagart 29.6 mm Whitechurch 0.8 mm, Wittering 11.2h Valley 6.3h) [Max 18.2C Min 13.9C Rain 0.3 mm]. A fine fresher morning on the 23rd with broken cumulus clouds increasing. The temperature at 0141 GMT was 15.6C, but had then fallen to 12.3C at 0830 GMT and at 0900 GMT was 14.2C. Pressure 1020 mb was rising, there were cold fronts across Scotland associated with low 988 mb Norwegian Sea and 990 mb SE Greenland, and the long meandering one over Wales with Atlantic low 1002 mb A of Greenland. Little in the way of brightness through the day 220W at 1229 GMT was the best. A red admiral butterfly was spotted wings open on soil between vegetable rows in the garden for a long time in the afternoon, the warmest place it could find (Wellesbourne 23.5C Usk 21.9C Capel Curig 16.0C Lerwick 10.4C, South Newington 6.5C Swyddffynnon 10.0C, Cassley 29.0 mm Swyddffynnon 3.2 mm, Wattisham 10.6h Lake Vyrnwy 8.4h Valley 3.6h) Max xx Min 13.3C Rain 0.3 mm]. The 24th began unpromisingly with grey overcast sky, moderate misty visibility and intermittent drizzle. There were patches of blue sky to the NW seen from Rhosneigr and over Red Wharf Bay seen from Moelfre. It had been cooler overnight, but in the morning though breezy it felt warmer. The sky cleared here and the afternoon was sunny and warm (Brize Norton 25.3C Hawarden 24.9C Mumbles Head 17.6C Lerwick 12.9C, Swyddffynnon 5.0C, Baltasound 14.6 mm Gogerddan 2.2 mm, Manston 11.4h Aberporth 5.3h Valley 3.7h) [Max 21.0C Min 12.5 Rain 0.2 mm].

It was very mild overnight with the air minimum temperature 15.9C on the 25th at 0147 GMT. SKIRON Graphic courtesy of the University of Athens.There was an incursion of warm air over Britain from the Mediterranean region and at 0900 GMT it was 16.7C. The sky was overcast and low cumulus clouds were seen close to the mountains in the west of the range. Pressure was on 1013 mb, there was a ridge over the North Sea, but it was declining. Complex low 989 mb SE of Iceland and isobars were lightening close to NW Scotland with winds strengthening. Pressure was high 1024 mb in the Adriatic region while there was a low 1010 mb over the Bay of Biscay. Warm fronts were situated over the North Channel and NW Scotland. The sun broke through at 1030 GMT and there was a glimpse of sunshine otherwise it was dull, but the day kept dry (Tibenham 23.9C Hawarden 22.9C Aberdaron 17.1C Lerwick 14.6C, Aboyne 3.0C Libanus 14.0C, Achnagart 9.2 mm Pembrey Sands 2.8 mm, Herstmonceux 4.8h Lake Vyrnwy 1.7C Valley 0.1h) [Max 19.5C Min 15.9C Rain nil]. Heavy rainfall in North Wales 24 h up to 09 GMT on the 27 Sept 2021.Mostly cloudy on the 26th after a fine bright start. A few glimpses of sunshine seen during the day which was breezy the S'ly force 5 at times. Sunnier later in the afternoon then heavy rain 27 mm/h on a cold front at 2240 GMT. Rain continued light to moderate with the wind moderated (Monks Wood 23.5C Hawarden 21.2C Lake Vyrnwy 16.1C Lerwick 13.9C, North Wyke 8.2C, Tyndrum 26.2 mm Valley 6.6 mm, Kirkwall 7.0h St Athan 4.7h Valley 2.1h) [Max 18.8C Min 14.2C Rain 31.2 mm]. Rain continued after midnight on the 27th turned heavy again 0140-0210 GMT again falling at a rate of up to 27 mm/h then intermittently moderate to heavy before easing by 07 GMT. Rainfall in the 24-h to 0900 GMT was 31.2 mm, largest of the month and in September since 2012 when 49.5 mm fell on the 24th. Gorwel Heights in Llanfairfechan had 38.0 mm, largest of the month (graphic above left). Cumulonimbus clouds were reported in the vicinity and along with crepuscular rays made for a dramatic sky scene. SKIRON Graphic courtesy of the University of Athens.The sky was clearer in the NW and with very good clear visibility cleared here during the morning to give a sunny though breezy and cooler than of late afternoon. Cold polar air was beginning to encroach from the north-west (see SKIRON model graphic left). There was a heavy shower of rain and ice pellets at 1718 GMT that fell at a rate of up to 77 mm/h brought the rainfall total to 29.0 mm (00-00) (Bournemouth 18.9C Cardiff 17.4C Tredegar 13.9C Wick 10.1C, Castlederg 6.4C Libanus 8.0C. Kinloss 38.8 mm Valley 38.4 mm, Aberdaron 8.8h Valley 7.7h) [Max 15.3 Min 9.1C Rain 12.0 mm]. Dull, wet and cooler on the 28th as polar air encroached meeting the warmer southern air. Pressure 1011 mb was falling with low 969 mb over the Baltic there was a cold front lying from Norway over the Baltic to France. We had active shower troughs off the Atlantic to the NW in circulation around Iceland region low 981 mb. There was a torrential downpour of rain with gusty wind at 0305 GMT that fell at a rate up to 303 mm/h waking me up. We had more showers and glimpses of sunshine through the day. An active thunder shower moved along the mountains and Menai Strait from Caernarfon Bay and thunder was heard from 1840 GMT for about 15 mins as it passed to the southeast. It continued towards Llandudno and on to Rhyl before fizzling out (Coningsby 19.4C Mumbles Head 15.5C Sennybridge 10.8C Eskdalemuir 9.9C, Redesdale 3.2C Llysdinam 6.3C, Okehampton 39.8 mm Sennybridge 28.6 mm, Kirkwall 8.8h Aberdaron 2.7h) [Max 13.1 Min 9.2C Grass 6.1C Rain 8.8 mm] Cooler air and some clear sky overnight resulted in the lowest grass minimum reading 3.8C since 27th May that was 2.5C. With a scattering of brown fallen leaves on the ground on the morning of the 29th and an air temperature of 10.1C it seemed autumn had arrived. Cumulus clouds at 3 oktas cover were increasing and by 10 GMT the sky was mostly cloudy. A fair breeze the WSW'ly force 4 in the trees. Sunny at times in the afternoon when it felt quite warm giving the feeling that summer was not giving up just yet Planted out a row of spring cabbage from potted plants as the soil is still warm they should get away quite well. Today was the first day that soil temperature gradient was highest deepest in the profile. They were lowest 10.1C at 5 cm; 11.2C at 10 cm; 13.2C at 20 cm; 14.5C at 30 cm; 15.3C at 50 cm and highest 15.9C at 100 cm (Scilly 17.0C Cardiff 16.2C Libanus 12.0C Dalwhinnie 10.5C, Kinbrace -0.7C Sennybridge 4.3C, Myerscough 25.8 mm Hawarden 13.4 mm, Wittering 9.3h St Athan 9.2h) [Max 15.1C Min 7.0C Grass 3.8C Rain 10.2 mm]. The 30th began poorly with slight rain and a gusty force 5/6 SW'ly wind. There had been rain overnight, some moderate to heavy around 0240 GMT. In mist and rain visibility was poor. Strong winds around the coast Mumbles Head 54 mph and Aberdaron 52 mph made for big waves on the shores of Anglesey. Picked up some Bardsey apples that had fallen in the wind, they are just right for eating now (Hawarden 18.3C Tredegar 14.4C Lerwick 11.5C, Aboyne -1.4C Tredegar 4.5C, Capel Curig 45.6 mm, Lerwick 3.1h Hawarden 0.1h) [Max 15.9C Min 9.9C Grass 5.6C Rain 9.9 mm].

The month ended with a mean temperature 15.9C (+2.1) & [+1.9], highest since 2015 and ranking 2nd highest in September station records. Minima were at a record high, the mean 12.7C [(+2.0)]. Rainfall of 113.7 mm was (109%) & [112%] of averages largest since 2019 ranking 38th in Llansadwrn records since 1928. A duller than average month on Anglesey with 3.9h sunshine per day four sunless and ranked 44th since 1931.

 



Home page Site map Top Home page Site map Top

October 2021

October 1 - began fine and bright, but there was a chill in the air of a moderate WSW'ly breeze. Pressure 1005 mb was rising quickly with low 974 mb S Iceland's associated cold fronts were eastward having passed over in the night. Snowberry berries. Snow on the way?Showers heaviest 0219 GMT had a burst falling up to 12.6 mm/h all liquid it seemed, but as the snowberry has white berries developed is it not time for some snow on the mountains? An October red admiral on Michaelams daisy in our garden at Gadlys, Anglesey.It has small rather insignificant pink flowers in summer and it produces the white berries in the autumn. The berries are round, fleshy and last well after the shrub has shed its leaves. Certainly it seems fresher this morning, the transition to autumn has occurred fairly suddenly this year, usually it is a drawn out intermittent phenomenon. Summer hadn't quite finished as a pristine red admiral butterfly was spotted on the Michaelmas daisy now in full flower in the garden. Sunny spells and light showers in the afternoon and turning a bit colder (Santon Downham 19.0C Cardiff 16.1C Lake Vyrnwy 11.3C Tyndrum 9.5C, Kinbrace -0.1C Lake Vyrnwy 9.0C, Achnagart 38.0 mm Swyddffynnon 27.0 mm, Aberdaron 9.0h) [Max 13.7C Min 9.9C Grass 7.5C Pptn 11.8 mm]. Heavy showers overnight, rain and ice pellets, one at 0333 GMT had a burst of 38.6 mm/h. The morning of the 2nd began overcast and dull with light rain and poor visibility. The complex low between Iceland and Scotland was 977 mb and here pressure 993 mb was falling quickly reaching 986 mb at 1738 GMT. There was no improvement through the day that was sunless (Manston 17.7C Mumbles Head 14.7C Lake Vyrnwy 10.3C Dalwhinnie 8.3C, Drumnadrochit 1.6C Llysdinam 3.9C, Milford Haven 39.2 mm, Lerwick 5.4h Aberporth 0.1h) [Max 12.1C Min 8.5C Grass 7.0C Pptn 15.0 mm]. After a chilly night with air minimum down to 6.6C, lowest since 27th May (6.1C), and 3.3C on the grass, it was feeling fresh on the morning of the 3rd. Cumulus clouds were increasing at 0900 GMT, fine and breezy with a WSW'ly force 5, good visibility. Pressure 998 mb was rising quickly. Deep low 968 mb Shetland was dominating a large area from Iceland to the Baltic and France. A few cumulonimbus were over N England, Cornwall and the south-west. Pressure was high 1034 mb Russia and 1029 mb Azores. Mostly sunny (St James Park 18.2C Valley 16.5C Lake Vyrnwy 11.9C Dalwhinnie 9.5C, Resallach -0.9C Llysdinam 2.6C, Kinlochewe 30.6 mm St Athan 10.4 mm, Edinburgh 8.2h Aberdaron 7.2h) [Max 14.3C Min 6.4C Grass 3.3C Rain 4.5 mm]. One of the red squirels at the feeder in our garden at Gadlys, Anglesey.Cloud cover was variable on the the 4th first decreasing, then increasing producing a heavy shower at 0849 GMT before reducing again. At 0900 GMT the shower had nearly stopped when the temperature was 10.9 C and visibility still poor. The morning kept mostly cloudy, but there were sunny spells that were longer in the afternoon. A MetO yellow warning had been issued for S, W and NW Wales between 16 and 03 GMT. It did rain here overnight, but not excessively, further S larger amounts fell and there was flash flooding in places including S Wales and London (Heathrow 18.1C Cardiff 16.1C Libanus 11.2C, Aboyne 2.3C Llysdinam 5.8C, Levens Hall 52.0 mm Pembrey Sands 40.0 mm, Kirkwall 8.3h Valley 6.4h) [Max 14.4C Min 9.0C Grass 5.4C Rain 14.2 mm]. METO analyis chart for 0000 GMT on 5 October 2021: Crown Copyright (c).Pressure dropped to 994.5 mb at 0155 GMT as the depression passed over, recently calm the NW'ly breeze was picking up at 0900 GMT on the 5th and it was fine with good visibility. Pressure was 1001 mb was rising rapidly with low 992 mb then on the east coast heading into the North Sea. Atlantic hurricane SAM was <960 mb S of Greenland and there was a ridge west of Ireland. The wind veered W'ly later in the morning and the rain turned moderate to heavy (30 mm/h 1302 GMT) ceasing around 14 GMT. A dull and damp afternoon (Shoreham 16.5C Usk 15.7C Lake Vyrnwy 11.2C Spadeadam 8.4C, Altnaharra -0.8C Lake Vyrnwy 7.1C, Chillingham Barns 73.6 mm Usk 21.2 mm, Tiree 7.7h Aberdaron 5.2h Valley 4.0h) [Max 12.2C Min 9.1C Rain 14.2 mm]. Hurricane SAM downgraded to tropical storm was 968 mb SE Greenland tracking towards Iceland and should give stronger winds in the NW tomorrow. It was feeling fresh at 0900 GMT on the 6th with moderate visibility but bright with some sunshine breaking through, pressure had risen to 1020 mb in a ridge over the UK with 1028 mb N Spain. The afternoon bright at first turned dull by 14 GMT with intermittent slight rain and becoming breezy (Gosport 18.4C Usk 18.0C Lake Vyrnwy 13.4C Fair Isle 10.5C, Braemar 0.7C Bala 6.2C, Fylingdales 27.4 mm Porthmadog 5.4 mm, Reading University 9.7h Lake Vyrnwy 3.9h Valley 3.0h) [Max 16.1C Min 8.2C Grass 5.1C Rain 1.3 mm]. SKIRON Graphic courtesy of the University of Athens.It was mild and damp on the 7th with warm moist air from the south. It was raining slightly and in the mist visibility was poor, mosses in the wood were loving it. Pressure was steady on 1021 mb with low 976 mb S of Iceland and 250 miles W of Rockall. Pressure was high 1028 mb over France while low 1006 mb Italy. The warm front was over the North Sea and the cold front over Ireland. The day was dull, damp and breezy (Hawarden 21.8C Gorwel Heights 20.7C Tredegar 15.4C Baltasound 13.3C, Baltasound 3.2C, Dunstaffnage 33.0 mm Capel Curig 12.0C, Weybourne 7.1h St Athan 1.5h) [Max 16.2C Min 11.1C Rain 0.2 mm]. Much the same on the 8th at 0900 GMT, although there had been a glimpse of sunshine earlier. It was then dull, but still mild 15.8C. Dry in the afternoon with a little sunshine at first. Transferred the autumn flowering chrysanthemums, that had been growing outside in 10 in pots all summer, into the greenhouse. The large buds of earliest flowering variety Lilian Shoesmith was starting to break (Ryhill 21.7C Hawarden 20.6C Tredegar 15.8C Little Rissington 14.2C, Tain Range 8.1C Bala 9.3C, Killowen 17.4 mm, Leconfield 8.4h Hawarden 4.0h) [Max 18.4C Min 14.0C Rain tr]. Dull with overcast sky on the 9th and thick low cloud producing a little drizzle. It continued mild the temperature at 0900 GMT 14.9C and just 90W of light. Pressure 1028 mb was rising with low 995 mb SE Greenland with a cold front over Ireland. This moved over the Irish Sea as a slow moving band of rain reaching here about noon with drizzle and slight rain. As the front progressed eastward in the high pressure precipitation reduced. A dull and sunless day (Herstmonceux 21.1C Cardiff 19.3C Llansadwrn 15.7C Fair Isle 13.3C, Frittenden 3.6C Capel Curig 9.1C, Harris Quidnish 25.6 mm Mona 0.8 mm, Shoeburyness 9.7h St Athan 3.6h) [Max 15.7C Min 12.7C Rain 0.6 mm].

Little in the way of clouds to start the day on the 10th, diminishing cumuli over mountains to the south. Visibility was moderate to good, a bit misty still after low-lying mist on fields and in valley bottoms early on. Overnight air temperature 8.9C with 5.5C on the grass. An October comma butterfly in our garden at Gadlys, Anglesey.Pressure 1032 was rising in high 1034 mb just 50 miles W of Shannon. A cold front was lying over central England, there was mist and some rain in SE England and fog in Kent. Here the wind was variable, generally N, by 0915 a few cumulus clouds developed overhead before clearing again. A very fine and sunny day. Two red admiral and a comma butterfly all afternoon on Michaelmas daisy (Cardiff 20.7C Aberporth 14.7C Dalwhinnie 10.5C, Aboyne 1.0C Sennybridge 6.5C, Cassley 10.4 mm, Shobdon 9.0h Aberdaron 8.4h) [Max ]. Cloudier on the 11th as pressure 1034 mb continued to rise in the Irish high. The warm air from the S was today displaced with fresher northern Atlantic air, weak sunshine with sunny spells developing. Took down the row of runner beans, saved what beans were left for the kitchen and put canes in the shed. Pleasant working in the garden, three red admirals seen today (Pershore 18.0C Cardiff 17.8C Swyddffynnon 14.2C Baltasound 9.1C, Swyddffynnon 1.6C, Resallach 30.0 mm, Camborne 8.1h St Athan 7.4h) [Max 15.6C Min 8.1C Rain nil ]. The sky was overcast at first on the 12th with light SSW'ly wind. Pressure had reduced to 1028 mb the high 1031 mb over Cork, Ireland. A cold front over Scotland associated with low 1012 mb SE Greenland was producing some rain in Northern Ireland and N England. Apart from a few spots here at 0920 the day was fine with some sunshine breaking through at times. Picked remaining Bardsey apples as interest was being taken in them by jays. They will store for only a few weeks, if they last that long (Cardiff 18.3C Swyddffynnon 13.6C Fair Isle 9.5C, Wick 1.2C Pembrey Sands 2.5C, Altnahinch 13.8 mm Mona 1.4 mm, Lerwick 5.3h St Athan 3.8h) [Max 14.4C Min 9.3C Grass 4.2C Rain 1.2 mm]. A dark and damp day on the 13th, calm at first with anemometer not turning and smoke rising vertically. High 1029 mb over the Celtic sea with a warm front down the spine of the UK associated with low 1001 mb Iceland, low 1009 mb central Med. Slight rain and or drizzle at times, sunless (Exeter 18.7C St Athan 17.0C Mona 12.9C Dalwhinnie 11.3C, Marham 0.1C Sennybridge 4.1C, Lerwick 6.6 mm Aberdaron 1.4 mm, Camborne 10.0h St Athan 4.3h) [Max 12.9C Min 11.9C Grass 4.3C Rain ]. On the 14th the high was sinking south and pressure here 1023 mb falling. The high was still giving good weather in southern England and as far as N Italy. Low 988 mb was over the Norwegian Sea and there was a cold front off N Scotland heading south and arrived here about midnight (Heathrow 19.3C Cardiff 17.7C Lake Vyrnwy 12.6C Spadeadam 11.2C, Pembrey Sands 5.7C Yeovilton 4.1C, Kinlochewe 18.4 mm, Camborne 7.3h St Athan 5.0h) [Max 14.6C Min 11.0C Grass 9.2C Rain 1.1 mm]. The cold front gave a little rain and by the morning of the 15th had passed over. Almost clear sky at 0900 GMT with a fresher feel, very fine and sunny with very good visibility. No ice precipitation here or on the mountains (Cardinham 18.3C Whitechurch 18.0C Lake Vyrnwy 11.3C Loch Glascarnoch 7.0C, Bala 6.0C Tyndrum -1.1C, Loftus 6.6 mm Capel Curig 1.4 mm, Morecambe 9.8h Valley 9.3h) [Max 14.3C Min 8.0C Grass 4.5C Rain nil].

The first 15-days temperatures were above the averages the mean temperature 14.8C (+1.0) & [+0.8]. Rainfall of 56.2 mm was [(44%)] of averages. Sunshine at RAF Valley averaged 3.1 h per day.

A fine and dry morning on the 16th with pressure on 1019 mb. Overnight air minimum 6.6C and down to 1.8C on the grass lowest since 8th May (1.6C). A lingering detached frontal band lay over Ireland, Wales and SW England and was thick enough to produce a little rain in a few places, somewhat warmer air was again encroaching from the south. Brighter before noon, a pleasant fine and dry day with some sunshine (Cardiff 18.3C Lake Vyrnwy 13.9C Kielder Castle 7.4C, Capel Curig 2.3C Redesdale -3.6C, Dunstaffnage 13.2 mm, Bournemouth 7.3h St Athan 4.0h Valley 0.6h) [Max 15.3C Min 5.9C Grass 1.8C Rain 4.8 mm]. It was dull and a rather wet morning on the 17th with a moderate S'ly breeze. Slight rain and drizzle resulted in poor visibility. A small depression 1005 mb was lying near Malin Head, pressure here was 1012 mb and here was a frontal band over the Irish Sea. Thick cloud all day, sunless with low solar radiation levels, brightest at 1125 GMT only 54W m -2 (Cardiff 19.5C Lake Vyrnwy 12.5C Lerwick 9.1C, Baltasound 1.0C, Eskdalemuir 25.0 mm Capel Curig 23.2 mm, Stornoway 7.3h St Athan 5.8h) [Max 15.8C Min 11.8C Rain 1.4 mm]. Much the same on the 18th with the warm moist tropical air arriving over the Atlantic from the Gulf of Mexico producing rain in the west. Moderate to heavy rain and a moderate S'ly wind. Pressure was on 1010 mb and with complex Atlantic lows 980 mb S Iceland a series of frontal bands was lined up to give us more wet and windy weather. The temperature at Gorwel Heights enhanced by Föhn wind reached a remarkable 21.1C at 1439 GMT compared with 16.9C here in Llansadwrn Gorddinog AWS reported 20.8C (Gorwel Heights 21.1C Castlederg 19.0C Rhyl 18.5C Tredegar 14.7C Lerwick 11.2C, Wisley 4.4C Llysdinam 7.0C, Plymouth 17.6 mm St Athan 15.0 mm, Boulmer 1.1h Hawarden 0.1h) [Max 16.7C Min 12.8 Rain 8.7 mm]. Very wet and windy on the 19th with moderate fog visibility < 500 m at 0900 GMT. Recent moderate to heavy rain easing through the morning, but heavy again in the middle of the afternoon heaviest 18 mm/h at 1500 GMT. Sunless maximum solar radiation 98 W m -2 at 1052 GMT (Santon Downham 21.0C Hawarden 20.1C Gorwel Heights 19.5C Tredegar 15.2C Lerwick 12.3C, Fyvie Castle 9.2C, Dunstaffnage 45.2 mm Capel Curig 36.0 mm, Shoeburyness 3.1h Hawarden 0.2h Valley 0.0h) [Max 16.4C Min 13.9C Rain 15.3 mm]. Pressure 994 mb was falling quickly on the 20th with low 996 mb over St. George's Channel having an occluded front over Anglesey. Very wet with heavy showers 33 mm/h at 0801 GMT, there was standing water for the first time in a while. There was flash flooding in S Wales at Kidwelly, Gorseinon and Swansea (Heathrow 19.1C Cardiff 17.2C Llansadwrn/ Mona 11.4C Baltasound 7.1C, Katesbridge 3.5C Mona 6.2C, Wiggonholt 52.0 mm Pembrey Sands 29.0 mm, Brize Norton 6.1h St Athan 4.9h Valley 1.1h) [Max 11.4C Min 9.2C Grass 2.5C Rain 11.8 mm].

On the morning of the 21st there was a moderately heavy shower of rain and large ice pellets (4-6 mm diameter) at 0615 GMT that mostly covered the ground and the liquid state fell at a rate of up to 33 mm/h, the solid state took a little while to melt in the AWS gauge with some remaining in house roof gutters till afternoon. Pressure 1011 mb was rising quickly at 0900 GMT when the temperature rising from a minimum of 5.4C lowest of the month, was 7.4C and that rising to 11.4C at 1250 GMT, together with yesterday were the lowest maxima of the month. Frequent showers were heading through the North Channel and reaching Anglesey and the Snowdonia Mountains where, in the afternoon, a sprinkling of snow was seen on Yr Wyddfa and Garnedd Ugain. A cooler fresher showery day than of late (Cardiff 15.1C Lake Vyrnwy 9.6C Lerwick 6.4C, Aviemore -1.4C Sennybridge 1.2C, Charsfield 23.4 mm Capel Curig 9.0 mm, Waddington 9.1h St Athan 9.0C Valley 5.3h hours) [Max 11.4C Min 5.4C Grass 2.5C Pptn 2.1 mm]. A showery day on the 22nd the convective clouds off the sea to the NW continuing. Pressure 1020 mb was rising with a ridge from the Azores to SW Ireland. More cloud and fewer sunny intervals today. A particularly vigorous shower of rain at 1500 GMT resulted in the temperature falling 4.3C from 12.8C the day's maximum to 8.5C (Pershore 15.7C Cardiff 14.6C Libanus 10.2C Lerwick 7.5C, Benson 0.9C Sennybridge 2.4C, West Freugh 6.4 mm Gogerddan 5.8 mm, Leuchars 6.2h Hawarden 4.0h Valley 2.8h) [Max 12.8C Min 6.1C Grass 2.1C Rain 2.1 mm]

The unsettled wet theme continued on the 23rd with early showers of rain, there had been no hail. Pressure was on 1020 mb, the ridge had moved over the North Sea and isobars were tightening in the NW between European high 1030 and Icelandic low 978 mb. At 0900 GMT the sky was overcast with a slight shower in progress, it was fairly bright then darkened. Visibility was poor to moderate at times and it was breezy with a moderate to strong WSW'ly. Temperature near midnight was 12.4C (Herstmonceux 15.5C Gorwel Heights 14.3C Rhyl 13.8C Tredegar 9.6C, Aboyne -3.1C Lake Vyrnwy 5.7C, Dunstaffnage 20.2 mm Mona 2.8 mm, Sheffield 1.2h Hawarden 0.4h Valley 0.2h) Max 12.4C Min 8.4C Rain 1.4 mm]. It was a blustery morning on the 24th with slight rain and showers with crepuscular rays lightening the dark sky in places. There was a frontal band over the Irish Sea between low 980 Iceland and high 1035 mb SE Europe. Breezy still, but some sunny spells and drier spells. Gorwel Heights 15.7C Gorddinog 15.6C (Chivenor 17.5C Cardiff 17.1C Lake Vyrnwy 11.8C Fylingdales 10.5C, Alice Holt Lodge 7.0C Lake Vyrnwy 8.2C, Threave 38.4 mm Whitechurch 140 mm, Manston 5.7h Valley 4.3h ) [Max 14.4C Min 10.8C Rain 5.3 mm]. Fine and bright on the morning of the 25th although mostly cloudy with altostratus and cumulus that were increasing. Pressure on 1012 mb was rising with complex low 980 mb in the region of Iceland but cloud was thickening. Sunny spells in the afternoon (St James Park 17.7C Cardiff 16.1C Libanus 12.4C Dalwhinnie 7.9C, Fyvie Castle 4.7C Lake Vyrnwy 7.5C, Achnagart 27.4 mm Cardiff 16.8 mm, Kinloss 7.0h Aberdaron 5.9h) [Max 13.2 C Min 9.1C Rain 1.4 mm]. Pressure 1012 mb was steady on the 26th with low 963 mb SE Greenland. There was an occlusion over the Irish Sea and a warm frontal band over Ireland. It was mild at 0900 GMT 13.2C in warm moist Atlantic air from tropical regions. Breezy with moderate misty visibility and recent light rain. There was a little blue sky overhead and not much in the way of sunshine through the day. The temperature rose to 15.6C after midday thereafter in the warm air hovering around 14.8C through the afternoon and evening (Exeter 17.7C Hawarden 17.4C, Tredegar 12.6C Fair Isle 12.3C, Kielder Castle 2.1C Bala 5.3C, Achnagart 73.4 mm Capel Curig 22.0 mm, Manston 2.7h Valley 1.7h) [Max 15.6C Min 9.3C Rain 6.4 mm].

Wet and windy all day on the 27th beginning with strong to gale SW'ly poor visibility rain and mist. The wind had reached 40 mph in the night and 61 mph in Capel Curig and there was heavy rain at 0526 GMT. Low 962 mb was SW Iceland and with pressure high 1031 mb N Adriatic isobars over the UK were tight with pressure here on 1009 mb falling through the day. Rain continued moderate to heavy until evening when showery into the night (Chillingham Barns 18.4C Hawarden 18.1C Okehampton 12.7C Tredegar 12.9C, Fyvie Castle 6.7C, Shap 69.2 mm Capel Curig 34.6 mm, Shoeburyness 4.4h Hawarden 0.5h) [Max 15.1C Min 13.2C Rain 43.5 mm Capel Curig 46.8 mm]. Wet and windy weather continued on the 28th with pressure 1000 mb still falling. Low 969 mb was S Iceland with a frontal band over the Celtic and Irish Seas delivering pulses of moderate to heavy rain and squally wind. Rain fall in the 24h to 0900 GMT was 43.5 mm, largest daily fall of the month and since 23 February. The strong gusty S'ly wind blew over a large beech tree in the garden at 1145 GMT. By afternoon it had cleared up and was sunny though still windy (Santon Downham 17.3C Cardiff 16.7C Lake Vyrnwy 12.4C Loch Glascarnoch 11.0C, Altnaharra 4.4C, Eskdalemuir 84.8 mm Valley 54.8 mm, Wattisham 8.4h St Athan 0.8h) [Max 14.8C Min 13.4C Rain 35.6 mm Valley 41.0 mm Capel Curig 28.2 mm]. Heavy rainfall event in North Wales 27-31 October 2021.It was raining hard on the 29th at 0900 GMT falling at a rate of up to 65 mm/h. Rainfall for the past 24h was 35.6 mm. second largest of the month. The ground was saturated and there was local flash flooding caused by runoff from fields (Kew Gardens 16.5C Usk 15.2C Libanus 10.4C Dalwhinnie 7.5C, Tain Range 3.2C, Whitechurch 45.6 mm, Magilligan 4.4h Aberdaron 4.1h) [Max 12.3C Min 10.7C Rain 23.6 mm]. A much better day on the 30th after an early shower there was an almost clear sky at 0900 GMT and very good visibility. Rainfall for the past 24h was 23.6 mm, third largest of the month bringing the total for the last 3-days to 102.7 mm. Pressure 991 mb was rising, after bottoming at 988.9 mb at 0428 GMT, with complex low-pressure to the W and NW (977 mb Iceland). Pressure was high 1035 mb just N of the Black Sea. The day was sunny and fine with fresher air from the north. There was extensive flooding of the Cefni marsh (Kew Gardens 15.8C Cardiff 15.0C Libanus 10.2C Killylane 8.6C, Aboyne 1.9C, Porthmadog 36.2 mm, Aberdaron 7.5h) [Max 12.1C Min 7.7C Rain 11.5 mm Gorwel Heights 25.2 mm]. After a prolonged heavy shower of rain 28 mm/h at 0652 GMT and gusty wind on the 31st the sky was clearing at 0900 GMT with some cumulus clouds developed over the Snowdonia Mountains. At Gorwel heights 25 mm of rain had fallen since midnight and at 0621 GMT had fallen at a rate up to 92 mm/h. After the heavy rains the ground still had some standing water in places. Pressure 981 mb was again falling quickly with deepening low 975 mb Shannon, lowest pressure here was 976.5 mb at 13:54 GMT. A cumulonimbus cloud was spotted to the S of the station at 0930 GMT, some sferics were recorded over Cardigan Bay here there was was showery rain through the day (40.6 mm/h at 1331 GMT) with glimpses of sunshine (Kew Gardens 15.9C Cardiff 14.0C Libanus 9.5C Loch Glascarnoch 7.9C, Fyvie Castle -1.0C Llysdinam 3.1C, Machrihanish 58.0 mm Capel Curig 41.8 mm, Yeovilton 4.9h St Athan 4.4h Valley 2.1h) [Max 12.2C Min 8.2C Rain 18.0 mm Capel Curig 49.0 mm Gorwel Heights 24.8 mm].

The month ended with a mean temperature 12.0C (+0.8) & [+0.9], highest since 2017 and ranking 10th in station records. Rainfall of 249.1 mm was (196%) & [193%] of averages largest since 2008 ranking 13th in Llansadwrn records since 1928. A sunnier than average month on Anglesey with 2.7h sunshine per day, but 10 sunless days.

 



Home page Site map Top Home page Site map Top

November 2021

November 1 - a very dull and overcast morning with light to moderate rain and poor visibility. Pressure 984 mb was rising with low 971 mb near Aberdeen, Scotland. Sunny spells in the afternoon when a red admiral butterfly was seen about the garden (Heathrow 14.9C Usk 13.8C Lake Vyrnwy 8.6C Loch Glascarnoch 6.7C, Fyvie Castle 2.8C, Stonyhurst 47.0 mm Capel Curig 39.2 mm, Wattisham 8.2h St Athan 3.0h) [Max 10.1C Min 7.2C Rain 5.6 mm]. The coldest night for a while and with an almost clear sky at dawn on the 2nd there was a touch of ground frost -0.4C recorded by the grass minimum thermometer. It had been frost-free for 178 days since 7th May (-2.7C). It was cloudier at 0900 GMT and after a recent shower of rain it was misty with moderate visibility. This cleared later and the afternoon was mostly sunny before light to moderate showery rain developed in the evening (Gosport 15.0C Usk 13.8C Libanus 8.4C Loch Glascarnoch 7.5C, Benson -1.8C Usk -0.8C, Kinlochewe 21.2 mm Milford Haven 18.4 mm, Wattisham 8.2h Hawarden 6.2h) [Max 11.8C Min 4.0C Grass -0.4C rain 15.3 mm]. After midnight on the 3rd the showery rain turned heavier (21 mm/h at 0242 GMT) with ice pellets and unidentified ice precipitation later, there were nine showers overnight. In the morning cumulus and cumulonimbus clouds were in the vicinity and there was another heavy shower at 0927 GMT (27 mm/h). The afternoon had some sunshine with the odd shower thrown in (Chivenor 12.9C Usk 12.8C Lake Vyrnwy 7.7C Dalwhinnie 6.3C, Bournemouth -2.5C Usk -1.6C, Aberdaron 27.6 mm, Shoeburyness 7.5h Valley 4.7h) [Max 10.7C Min 6.4C Grass 2.2C Pptn 15.3 mm]. Meteosat MSG image (c) EUMETSAT at 12 GMT on 4 Novenber 2021, courtesy of Ferdinand Valk.Pressure 1019 mb was rising on the 4th with Atlantic-high 1030 mb to the W and low 995 mb N Adriatic resulting in a much cooler flow of air from the north. There was a cool breeze 6.8C, but it was fine and sunny with much cirrus and a few cumulus cloud brushing the mountaintops. There was extensive standing flood water on the Cefni marsh from the recent large rainfalls. Convergent convective clouds formed in a persistent line over the North Channel, Isle of Man, South Stack Anglesey, Pembrokeshire and Cornwall, sometimes dubbed the Pembrokeshire Dangler in recent years. Open celled marine convection lay to the NW and E over the North Sea (Scolton 11.7C Lake Vyrnwy 7.2C Balmoral 6.0C, Bridgefoot -1.7C Sennybridge -1.3C, Fylingdales 21.2 mm Scolton 9.2 mm, St Athan 8.3h Valley 4.3h) [Max 10.7C Min 6.7C Pptn 0.5 mm]. The 5th was overcast and dull with cloud on the mountaintops. Pressure was on 1027 mb with Atlantic-high 1033 mb to the SW and low 997 mb over the Gulf of Bothnia in the Baltic. It was fine, but damp and the afternoon similar with slight drizzle at times. Sunless () [Max 11.7C Min 6.8C Pptn 0.3 mm].

A mostly dull and blustery day on the 6th as pressure 1022 mb fell with low 985 mb S Iceland having associated fronts to the NW of Scotland and Iceland. By 0900 GMT gusts of 52 mph recorded at Malin Head, 46 mph in Capel Curig and 35 mph here. It was a drying breeze, the soil remains wet and there is still a lot of water standing on the Cefni marsh Sunny spells and light showers with a heavy on at 1717 GMT that fell at a rate up to 19 mm/h (Drumnadrochit 15.3C Rhyl 14.2C Tredegar 10.9C Lerwick 10.4C, Benson 4.2C Tredegar 7.5C, Cassley 48.8 mm Capel Curig 8.0 mm, Camborne 2.2h St Athan 0.9h) [Max 12.8C Min 9.1C Rain 4.0 mm]. A more of less clear sky overnight with bright stars and on the morning of the 7th it was fine and bright with a 6 okta covering of cirrus and contrails. It was sunny in NE Scotland, E and S England, and East Anglia to the E. Water remained covering much of the Cefni marsh (Chivenor 13.7C Cardiff 13.3C Lake Vyrnwy 9.4C Dalwhinnie 7.0C, South Newington 3.4C, Tredegar 4.8C, Cassley 16.2 mm, Liscombe 6.5h Valley 5.7h) [Max 12.6C Min 6.7C Rain 0.3 mm]. Overcast and dull on the morning of the 8th with cloud as low as 1500 ft in the west of the Snowdonia range and 2800 ft on the slopes of the Carneddau. Fine at first, there was a smell of burning plastics in the air, by 0930 GMT there was slight drizzle. There was a warm front over the Irish Sea and pressure here 1021 mb was falling. High 1027 mb was over the Atlantic off Cap Finisterre with low 993 was over the Baltic. A glimpse of a red sun in the west under the cloud sheet at sunset (Castlederg 16.7C Hawarden 15.3C Tredegar 11.2C Fylingdales 9.6C, Topcliffe -1.6C Usk 0.4C, Achnagart 29.6 mm Porthmadog 5.2 mm, t Wattisham 5.3h Hawarden 0.3h) [Max 13.4C Min 5.8C Rain 2.0 mm]. Much the same on the 9th overcast and dull with slight rain and drizzle, very poor visibility. It was wet all day, rainfall duration 21h, and sunless. A cold front was charted over Anglesey at noon (Nantwich 17.6C Hawarden 17.3C Tredegar 11.1C Dalwhinnie 9.7C, Aboyne 2.4C, Spadeadam 26.2 mm Capel Curig 21.4 mm, Tibenham 6.1h Hawarden 2.4h) [Max 13.4C Min 10.9C Rain 13.8 mm duration 21h]. The 10th was wet in many places, but by 0900 GMT it had stopped here although the sky didn't clear. The Cefni marsh looked drier today after recent flooding (North Wyke 16.0C Cardiff 15.4C Libanus 10.0C Killylane 7.0C, Balmoral -0.2C, Cardinham 10.6 mm Gogerddan 8.6 mm, Boulmer 4.8h Aberdaron 1.1h) [Max 11.4C Min 8.7C Rain trace].

Another dull day on the 11th, no sign of the sun again. Continuing mild today's maximum 12.6C. At 0900 GMT rain was in sight and there was slight rain by 0920 GMT. Pressure on 1021 mb was falling with lows 973 mb west of Ireland and 987 mb over the Norwegian Sea. A detached warm front lay over the Irish Sea (Kew Gardens 16.1C Cardiff 14.4C Lake Vyrnwy 9.7C Baltasound 7.2C, Kinbrace 1.5C, Lough Fea 10.6 mm Mumbles Head 3.2 mm, Odiham 4.2h Hawarden 0.8h) [Max 12.6C Min 7.3C Rain 5.;6 mm]. A wet and windy day on the 12th, slight rain nothing heavy, but made for a dismal day with poor visibility. There was a train of lows 986 mb off the Western Isles with low 957 mb S of Greenland following (Teddington 15.9C Hawarden 14.5C Tredegar 10.5C Loch Glascarnoch 9.0C Baltasound 4.4C, Tyndrum 40.2 mm Capel Curig 28.8 mm, St Athan 3.3h) [Max 12.6C Min 9.5C Rain 0.8 mm], The 13th began fine and a little bright, even a break in the clouds at 0900 GMT. Pressure 1018 mb was rising with a ridge of high-pressure extended to the UK from high 1023 mb over Spain. There were spits and spots of rain through the day with glimpses of sunshine (Cardiff 16.2C Libanus 10.9C Loch Glascarnoch 9.2C, Mona 8.0C Dalwhinnie 1.6C, Harris Quidnish 5.8 mm, Morecambe 8.0h Hawarden 0.5h) [Max 12.0 C Min 8.8C Rain 0.3 mm]. Slight rain early on the 14th, an overcast, fine and damp morning. Visibility was good the cloud at 2500 ft on the Snowdonia Mountains, but lifting to just above the tops at 1030 GMT. There was a light SSE'ly breeze, another sunless day (Altnaharra 15.8C Cardiff 14.5C Libanus 10.3C Strathallan 8.1C, Braemar -1.7C, Tiree 12.8 mm, Hawarden 7.4h) [Max 12.7C Min 8.9C Rain 0.2 mm]. It was calm at 0900 GMT on the 15th and it had just started to rain. Slight rain morning and afternoon, sunless. There are several red squirrels about the garden at present visiting the feeders and eating nuts or taking them away to bury (Holbeach 14.4C Milford Haven 13.4C Sennybridge 9.8C Fylingdales 8.1C, Rostherne 1.4C, Resallach 11.8 mm Scolton 5.8 mm, Kirkwall 5.3h Aberdaron 0.5h) [Max 12.1C Min 9.4C Rain 4.4 mm].

The first 15-days temperatures were nearly two degrees above averages the mean temperature 9.9C (+1.6) & [+1.9]. Rainfall of 58.6 mm was [(44%)] of averages. Sunshine at RAF Valley averaged 1.5 h per day having 6 sunless days.

The 16th continued dull and sunless except a glimpse at sunset when it appeared briefly in the west under the cloud sheet. Pressure was on 1021 mb with complex low 971 mb in the Iceland region. Frontal waves lay to the north-west of Anglesey (Exeter 14.3C Usk 13.2C Lake Vyrnwy 9.2C Dalwhinnie 8.5C, South Farnborough -1.1C, Achnagart 21.6 mm Pembrey Sands 5.4 mm, Wattisham 4.6h Valley nil]) [Max 11.1C Min 8.8C Rain 0.2 mm]. ...

11.3#



Home page Site map Top Home page Site map Top


Latest weather. Latest AWS observations
Last year's Diary. Last year's Diary, for previous Diaries consult the site map
Snowdonia Snowline. Snowdonia Snowline for the current season
Latest observations. Daily Observations, usually updated bi-monthly
Monthly & annual summary 2020.Monthly & annual summary with analyses 2021
Weather graphics. Temperature graphs, daily and monthly rainfall histograms, accumulated rainfall total and more, all on a page for 2021
Latest weather page. The observer's choice of forecasts, satellite imagery, severe weather, natural hazards and more

Designed and written by Donald Perkins: Copyright © 1998-2021

Disclaimer

llansadwrn-wx.co.uk

Top Back Site map Home page