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

Llansadwrn (Anglesey)

Latest Diary 2020

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    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 (provisional) maximum, minimum, rainfall and sunshine are usually 21-21 GMT. When averages are referred to (.) compares with the last decade and [.] with the new 30-y climatological average [1981 - 2010]. All data are subject to verification and amendment.


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    September 2020

    A wet and very windy morning on the 30th with gale force 8 S'ly wind at 08 GMT recorded at Valley and, if not for the shelterbelt trees here, it would be similar. As it was it was very blustery and raining moderately at 0900 GMT in a shower started just before. Pressure on 999.5 mb was falling rapidly with frontal-wave low 983 mb Rockall having frontal cloud along the western fringe. There was a warm front over Liverpool Bay and a cold front on Dublin and occluded front over Shannon all producing in turn some 'weather' over the Irish Sea. The afternoon was better, it did turn out sunny later. The best of the weather with sunny spells was in SE England (Manston 19.1C Valley 16.1C, Dalwhinnie 10.6C Lake Vyrnwy 12.3C, Redesdale Camp 1.6C, Whitechurch 33.4 mm, Wattisham 2.9h Valley 1.0h) [Max 15.1C Min 10.1C Rain 7.0 mm].

    September ending with a rainfall total of 71.5 mm (65%) & [75%] of averages, was the driest month since May and lowest in September since 2015. Also the sunniest since May with 158.8h recorded at RAF Valley most since 2015 ranking 13th in September on the Anglesey record since1931. Temperatures were near the normal with a mean temperature of 14.0C lowest since 2018, but ranking 17th in station records since 1979.


    October 2020

    October 1 - a bright and chilly morning, fine and sunny with just 2 oktas of developing cumulus clouds. Slightly misty good visibility with no snow on the Snowdonia Mountains. The temperature at 0900 GMT was 8.1C and it had been down to 1.8C on the grass. Storm Alex, named by Meteo France, was developing SW of Ireland expected to reach Brittany 991 mb at midnight with severe winds along the Channel coast and Cornwall. Pressure here 998.5 mb was falling. We had a sunny afternoon pleasant enough for a cup of tea and slice of buttered home-made #lockdown sourdough Bara Brith, in our still colourful garden. The 18.7C max temperature was nice and some red admiral and comma butterflies put in an appearance as well (Frittenden 16.8C Usk 15.3C, Katesbridge -1.4C, Lerwick 33.0 mm Swyddffynnon 10.8 mm, Dundrennan 10.7h Valley 8.2h) [Max 13.7C Min 5.8C Grass 1.8C Rain trace]. The 2nd began fine with a cold feeling NE'ly wind and just a patch or two of blue sky showing through stratocumulus overhead. Pressure 996 mb was rising with low 968 mb over Cherbourg. The cloud was thickening and we had spots of rain and drizzle around noon and a brighter spell with a glimpse of sunshine around 1330 GMT with a return of dull conditions with further drizzle all amounting to very little volume in the raingauge. The best of the weather was in Scotland and NE England where mostly sunny. In the south strong winds and some heavy rain associated with Storm Alex (Auchincruive 16.2C Hawarden 15.2C, Pennerley 9.6C Libanus 9.7C, Shap -2.4C, Liscombe 65.0 mm Wiggonholt, Sussex 58.2 mm Tredegar 34.0 mm, Kinloss 10.5h Valley 1.2h) [Max 14.4C Min 8.1C Grass 4.6C Rain 0.2 mm]. A miserable morning on the 3rd, very dull cold and damp, but it was not raining at first. We were not alone as most of the UK was generally wet and it started raining here soon after 0900 GMT and was continuous light to heavy through the day and night . Low 986 mb was over the Charente Maritime, France, pressure here 995 mb was falling. Fronts over Scotland were associated with a depression 993 mb between Iceland and Cape Wrath. Here an occlusion in trough W of Ireland associated with low 995 mb S Iceland. Pressure was high 1033 mb Azores and the result was high seas in Biscay and extreme weather in France where 115 mph was recorded on the western coast. In SE France a massive 450 mm rainfall left several valley villages devastated after flash flooding and landslides. Three deaths had been reported with 20 persons missing. Here heavy rain in the afternoon fell at rates up to 16 mm/h (4.2 mm in 1 h) and 33.6 mm total recorded over 23h duration. At Gorwel Heights in the 24h 00-00 GMT 60.6 mm fell and at Gorddinog 51.4 mm. Local rivers including the Aber were in full flood bursting their banks (Wiggonholt 16.6C Porthmadog 13.5C, Machrihanish 0.9C, Craibstone 66.0 mm Rhyl 18.4 mm, Thomastown 4.4h Valley nil() [Max 11.8C Min 10.8C Rain 33.6 mm]. The rain had just stopped at 0900 GMT on the 4th, it was very wet underfoot and the sky was grey. Pressure 979 mb was rising after a low of 978 mb just before 0700 GMT. Visibility was a misty moderate and there was a cooling, but drying NE'ly breeze. The storm low 977 mb was over central England with triple point over the N Irish Sea, weather was brightest in NE England and Scotland. The afternoon was dry enough with some weak sunshine to do some work on the vegetable plot, clearing away pea nets and tending the remaining tomato plants. Mountain magic still had some tomatoes left (Auchincruive 18.0C Hawarden 16.0C, Okehampton 6.1C Lake Vyrnwy 6.7C, Swyddffynnon 48.2 mm, Morecambe 6.0h Hawarden 1.8h) [Max 13.9C Min 8.4C Rain 2.8 mm].

    Overnight it had been partially cloudy with the moon visible at times, but on the morning of the 5th the sky was overcast with slight rain and drizzle. At 0900 GMT visibility was poor and misty, low 987 mb was over the North Sea and there was an occlusion over the Irish Sea. The morning continued wet, the afternoon was dull, but dry, the day sunless. Showery rain in the evening (Heathrow 18.5C Usk 15.6C, Loch Glascarnoch 4.6C Swyddffynnon 4.9C, Altnahinch 21.0 mm Capel Curig 15.4 mm, Lerwick 8.6h Aberdaron 0.3h) [Max 13.0C Min 9.7C Rain 13.2 mm]. On the 6th there was torrential rain at 0900 GMT falling at a rate of up to 60 mm/h. Visibility was very poor and there was standing water in places. Pressure was on 994 mb with a depression 988 mb over the western isles of Scotland. Frequent showers and glimpses of sunshine in the morning, brighter with sunshine later in the afternoon (Heathrow 17.4C Cardiff 15.8C, Katesbridge 3.5C, Rochdale 43.2 mm Swyddffynnon 26.8 mm, Manston 6.6h Valley 5.1h) [Max 14.4C Min 9.4C Rain 6.2 mm]. Pressure 1012 mb was rising on the 7th with a weak ridge over SW UK from Atlantic-high 1026 mb W of Iberia. A fine and bright day with good visibility and a light WSW'ly breeze and a maximum temperature of 15.2C. There was rain light to moderate from 1800 GMT the temperature falling to 10.5C at 2230 GMT (Teddington 17.4C Cardiff 16.4C, Aboyne 3.6C, Resallach 35.8 mm Scolton 12.8 mm, Wattisham 7.9h Valley 4.7h) [Max 15.2C Min 8.8C Rain 18.5 mm]. At midnight on the 8th as a frontal wave low 1002 mb steamed up the Irish Sea warm air was introduced and at 0030 GMT the temperature started to rise quickly in moderate to heavy rain reaching a high of 14.3C at 0256 GMT. By morning 18.5 mm of rain had accumulated. The temperature had then fallen to 10.0C in cooler air. A clearance could be seen in the west and after spots of rain the days brightened with some sunshine, with a few more spots, in the afternoon. The low had crossed Anglesey an was over Cheshire and pressure here 1010 mb was rising. In the shelter of the garden some red admiral and large white butterflies were seen on Michaelmas daisy (Writtle 19.1C Cardiff 16.5C, Kinbrace -0.1C, Capel Curig 37.4 mm, Dundrennan 8.5h Hawarden 5.2h Valley 3.8h ) [Max 12.9C Min 10.0C Rain 3.2 mm]. On the 9th there was a cold front passing over Anglesey and at 0900 GMT we were into cooler air the temperature 8.9 C after a minimum of 6.7C. Dull at first with convective cumulus clouds developing over the Snowdonia Mountains and off the Great Orme over Liverpool Bay. Some slight showers and sunny spells here while at Gorwel Heights there was a shower of ice pellets at 1557 GMT (Swanage 15.9C Cardiff 15.2C, Kielder Castle 1.1C Usk 2.0C, Achnagart 21.2 mm Trawsgoed 11.2 mm, Aldergrove 6.8h Hawarden 3.9h Valley 3.2h) [Max 12.3C Min 6.7C Grass 1.9C Rain 0.7 mm].

    The 10th began with broken cloud and a strong WNW'ly breeze the air coming from Polar regions. Although the temperature was 10.5C it felt much colder. Pressure 1023 mb was rising with an Atlantic-high 1037 mb lying to the SW. Complex low 1002 mb was over the Baltic while an occlusion associated with low 1011 mb Norwegian Sea lay over Scotland and the Isle of Man. A little snow had fallen overnight on Cairngorm, conditions were suitable for ice precipitation on the highest Snowdonia peaks around 0530 GMT, but with the tops cloud covered nothing was seen at 0900 GMT. A glimpse of sunshine, but mostly wet with slight rain or drizzle. Best of the weather was in S, SE and NE England. Tropical storm Delta increased to category H4 in a record short-time in the Gulf of Mexico before hitting Louisiana and other southern states when reduced to H1 (Armagh 15.5C Cardiff 15.3C, Dalwhinnie -0.1C, Resallach 22.8 mm Rhyl 11.6 mm, St Athan 7.1h Valley 0.9h) [Max 13.5 Min 5.4C Grass 1.2C Rain 3.9 mm]. On the 11th pressure had risen to 1028 mb with a ridge to Shannon 1032 mb from Atlantic-high 1040 mb W of FitzRoy. After some showers in the night the morning was fine and sunny. There was a NNE'ly breeze and a few cumulus clouds were bubbling up over the mountains. A mostly sunny afternoon (Cardiff 16.3C, Shap 0.9C, Capel Curig 9.4 mm, Rostherne 7.9h Hawarden 7.0h Valley 4.9h) [Max 14.9C Min 8.6C Rain 0.4 mm]. A dull and damp morning on the 12th, poor misty visibility with slight rain and drizzle. Pressure 1017 mb was falling quickly with occluded fronts, associated with low 1009 mb between Iceland and Scotland, lying Cape Wrath, Irish Sea to Biscay. A large area of high pressure 1036 mb was over the Atlantic to the west while the Med was dominated by low 1005 mb. There was a prolonged heavy shower between 11-12 GMT. The afternoon was brighter with a glimpse of sunshine () [Max 12.5C Min 8.9C Rain 10.2 mm]. There was light to moderate rain from 01-06 GMT on the 13th then light showers. Pressure 1013 mb was rising as low 1007 mb over the Humber moved over the North Sea. The sky cleared rapidly before 0900 GMT, it was fine and sunny with a chilly moderate N'ly breeze. Later cumulus clouds developed with sunny spells in the afternoon that was dry here, but there were showers in Llanfairfechan (Usk 14.6C, Eskdalemuir -0.8C, Capel Curig 21.8 mm, Tiree 9.0h Aberdaron/ Valley 4.6h) [Max 12.5C Min 6.7C Pptn tr dw]. Clear sky in the early hours of the 14th then rapidly turning cloudier before 0900 GMT. There was heavy dew on the grass with the minimum reading 4.5C and it was misty with moderate visibility. The afternoon dry and bright with sunny spells (Armagh 17.2C Usk 16.0C, Kinlochewe 1.4C, Chillingham Barns 15.0 mm Valley 1.6 mm, Aberdaron 9.3h Valley 7.5h) [Max 13.8C Min 8.6C Pptn tr dw]. A very fine day on the 15th with cirrus clouds and a few cumuli . Pressure was high steady on 1029 mb in a ridge extended from high 1035 mb over the Norwegian Sea. Good to very good visibility, sunny afternoon, but the NE'ly breeze felt cold (Usk 14.9C, Tyndrum -3.3C Trawsgoed 0.4C, Manston 7.4 mm, Aberporth 9.8h Valley 9.0h) [Max 12.6C Min 5.7C Grass 0.3C Pptn nil].

    The first 15-days of the month were at first wet then drier and colder. Rainfall of 93.0 mm (79%) & [72%] of averages, the large fall 33.6 mm on the 3rd accounting for most . The mean temperature 10.8C (-0.5) & [-0.1] of averages. Sunny with a mean of 3.7 hours a day.

    The 16th began very fine and bright with a cool E'ly breeze. The 5 oktas mostly altocumulus cloud cover had been decreasing, but convective cumuli were developing in a line across the Snowdonia Mountains. Pressure was steady on 1028 mb in a ridge extended from high 1035 mb Iceland and Norwegian Sea. A mostly sunny afternoon (Gosport 15.4C Whitechurch 15.1C, Shap -1.6C Whitechurch 1.7C, Wittering 3.8 mm Usk 1.0 mm, Camborne 8.6h Aberdaron 5.2) [Max 12.1C Min 7.0C Grass 2.8C Rain trace]. A bright fresh feeling morning on the 17th especially early on when quite sunny, but by 0900 GMT the sky had begun to cloud over. Frosty in the Glens of Scotland. Pressure was steady on 1025 mb with a weak ridge persisting from high 1042 mb in the region of Iceland. The temperature was 8.6C, there was some more sunshine in the afternoon when 12.0C was reached. Visibility very good (Bridlington 14.7C Trawsgoed 13.6C, Loch Glascarnoch -1.3C, Kinloss 5.4 mm, Aberdaron 8.0h Valley 4.4h) [Max 12.0C Min 6.9C Grass 2.8C Rain nil]. Some clear spells overnight and a bright and cold morning on the 18th the minimum down to 6.2C and 1.3C on the grass with just a slight dew. Pressure 1025 mb was keeping high in a ridge from France while low 1022 mb was SW of Ireland. Mostly sunny here. Picked the remaining crop of Bardsey apples except two I cold not reach even with an apple picker. The Michaelmas daisy is a fully in flower and still attracts butterflies when the sun comes out, Cosmos in many colours is good also this year and honeysuckles seems to have been flowering all summer into autumn. Best of the weather today central UK, Anglesey to the Humber (Killowen 15.3C Milford Haven 15.1C, Resallach -1.6C, Loftus 4.4 mm, Bude 5.3h Valley 3.0h) [Max 13.1C Min 6.2C Grass 1.3C Rain nil]. AWS temperature record at Gorwel Heights showing effect of Fohn wind at 2030 GMT on 19 October 2020.After the sunny days the 19th was disappointingly dull, but mostly dry. The light ENE'ly winds of recent days were replaced by something stronger from the SSW. A dull morning with the sky very grey, moderately high altostratus over the tops of the Snowdonia Mountains, but there were some cumuli beginning to develop in the west. Dry until 18 GMT when there was a slight shower of rain. During the evening a Föhn wind developed in Llanfairfechan when the temperature rose to 17.2C at Gorwel Heights and Gorddinog AWS at 2130-2140 GMT (Llanfairfechan 17.2C Kew Gardens 16.3C Cardiff 15.4C, Shobdon 2.0C, Tiree 72.8 mm Aberdaron 0.8 mm, East Malling 5.2h St Athan 1.5h) [Max 15.1C Min 8.2C Rain 0.5 mm]

    A fine, but windy morning on the 20th with moderate visibility. At 0900 GMT rain was in sight and we duely had a light shower at 0920 GMT. Meteosat MSG image (c) EUMETSAT at 12 GMT on 20 October 2020, courtesy of Ferdinand Valk.Pressure was on 993 mb with low 973 mb off SW Ireland. High 1036 mb was off Nova Scotia and high 1030 SE Europe squeezing the isobars over the UK. The wind was S'ly and this was bringing up some Saharan dust towards SE England, but it did not arrive here. Some sunshine at times and blustery in the afternoon the gust picking up dried fallen leaves around the house making small noisy whirlwinds (Kew Gardens 19.0C Gadlys Gardens 16.6C Hawarden 18.0C, Lerwick 6.3C, Harris Quidnish 51.2 mm Tredegar 18.0 mm, Morecambe 5.4h Aberdaron 3.1h Valley 2.8h) [Max 16.6C Min 11.1C rain 3.2 mm]. A poor start to the 21st with slight rain and drizzle, very dull with thick grey clouds covering the sky. Pressure was on 993 mb with the depression over the UK 987 mb. It was a wet morning in most places and it kept mostly cloudy. An afternoon in the greenhouse where the chrysanthemums were developing nice fat buds, the early autumn Lilian Shoesmith and Goldplate were already showing colour after earlier disbudding. There are still some Mountain Magic tomatoes ripening, but one of the cucumbers has surrendered to the colder nights (Edinburgh Botanic Gardens 17.3C Gadlys Gardens 14.2C Hawarden 15.7C, Lerwick 7.2C, Altnaharra 27.0 mm Tredegar 19.6 mm, Dyce 5.1h Aberdaron & Valley 1.5h) [Max 13.8C Min 12.1C Rain 0.5 mm].

    A dull morning again on the 22nd the sky had some structure today and there was an opening in the mainly stratocumulus with developing cumuli appearing. Moderate visibility after recent light showers of rain. Brightening through the cool morning with some glimpses of sunshine. Pressure 1006 mb was rising with the best of the weather in central and eastern England. Low 994 mb over the N sea off Aberdeen had occluded frontal cloud over the N Irish Sea (Teddington 18.3C Usk 14.5C, Scolton 4.2C, Craibstone 35.8 mm St Athan 2.8 mm, Manston 7.1h St Athan 4.2h Valley 0.1h) [Max 11.4C Min 8.6C Rain 1.6 mm]. The 23rd started overcast and dull with poor visibility and a fresh SSW'ly breeze, gale force on the tops of the Snowdonia Mountains. Pressure 1002 mb was falling with complex low 971 mb just SE of Greenland. Much nicer in the afternoon with sunny spells developing, a red admiral butterfly was spotted on the flowers remaining in the herbaceous border. Pleasant enough for a cup and tea and slice of sponge cake in the garden (Shoeburyness 17.0C Cardiff 14.6C, Baltasound -0.7C, Bridgefoot 16.8 mm Capel Curig 5.4 mm, Aldergrove 6.1h Aberdaron 4.7h Valley 3.5h) [Max 12.7C Min 8.1C Rain 3.0 mm]. A wet and windy day on the 24th after a rough wet night in the early hours the S'ly reaching force 9 at Valley between 02 and 04 GMT. Recent moderate shower of rain; the pressure 993 mb at 0900 GMT with low 953 mb just to the NW with triple point frontal cloud over the N Irish Sea. The western fringe was again taking the brunt of the weather, it was better in eastern parts. Spells of rain through the day, moderate to heavy through the night from 2300 GMT, 70 mm/h at 0211 GMT, 15 wet hours duration (Shoeburyness 16.5C St Athan 14.3h, Fyvie Castle 0.6C, Capel Curig 34.0 mm, Magilligan 6.8h Valley 0.1h) [Max 12.1C Min 8.3C Rain 24.3 mm]

    A fine morning on the 25th after the heavy overnight rain had cleared, there was slightly hazy sunshine with moderate visibility at 0900 GMT, cooler at 8.8C. The hailometer had been marked by ice pellets. Pressure 990 mb was rising with a low 962 mb off Cape Wrath having an active shower front with sferics observed stretching from the W Scotland, the Pennines to SE England. Convective clouds developed over Snowdonia and towering cumuli were seen far to the NE over Liverpool Bay likely in Cumbria. Here a nice sunny day, though a bit breezy. Late in the afternoon ice precipitation was seen above 2000 ft fallen on Y Garn, Carneddau (Cardiff 14.6C, Drumnadrochit -0.1C, Tredegar 32.2 mm, Valley 7.5h) [Max 12.5C Min 6.1C Rain 3.2 mm]. A mostly cloudy showery morning on the 26th with an ongoing shower at 0900 GMT visibility was poor. Pressure 994 mb was rising quickly with low 979 mb over Scotland having an occluded front over Wales stretching from the Severn estuary to the Tay, a ridge of high-pressure to the W of Ireland. Brighter in the afternoon, mainly dry with some sunshine (Herstmonceux 15.0°C Usk 14.3C, Shobdon 0.1C, Achnagart 34.0 mm Capel Curig 12.8 mm, Manston 7.1h Hawarden 5.0h Valley 2.3h) [Max 12.4C Min 8.6C Pptn 1.5 mm]. On the 27th pressure 989 mb was falling quickly at 0900 GMT. Low 941 mb to the NW was S of Iceland and W of Scotland and there was a triple-point trough over the Irish Sea. Overcast with a strong S'ly wind with rain in sight did not bode well for the day. There was a blustery shower at 0920 GMT and the morning kept dull with further showery rain heavier at noon falling at a rate up to 14 mm/h for a while. After 15 GMT there was a clearance and we had some sunshine for a while (Yeovilton 15.9C Rhyl 15.0C, Aboyne 0.3C, Capel Curig 16.4 mm, Lerwick 4.4h Aberdaron 2.3h Valley 1.1h) [Max 13C Min 7.4C Rain 4.2 mm].

    Pressure had steadied on 995 mb on the 28th and we had a fine, bright and breezy morning. Lows 955 mb S of Iceland and 975 mb N Sea. Significant high Atlantic waves at 0000 GMT on 28 October 2020, courtesy of the University of Athens.A stormy day in the S Wales and Gloucester area, a house in Carmarthen was struck by lightning and the roof set on fire. There were rough sea around the coasts, the weather was such that waves reaching western shores, particularly Ireland, had a long reach across the Atlantic resulting in high waves in excess of 12-14 m. Mostly cloudy, but with some sunny spells (Frittenden 14.4C Cardiff 13.2C, Lossiemouth 0.8C, Achnagart 49.4 mm Tredegar 21.6 mm, Weybourne 5.5h Hawarden 3.1h Valley 2.5h) [Max 11.7 Min 7.4C Rain 10.6 mm]. A very wet, windy and sunless day on the 29th beginning with heavy rain at 06 GMT. At 0900 GMT it was raining and 10.6 mm was measured, with standing water in places around the weather station, and there was a lot more to come. There was a warm front over the Irish Sea and a frontal-wave W of Shannon associated with low 966 mb SW Iceland. Pressure here 1004 mb was falling rapidly. It rained for 20h out of the 24h and by next morning 33.9 mm had fallen (09-09 GMT), the wettest day of the month just beating the 33.6 mm on the 3rd. In Capel Curig 88.0 mm fell with 36.2 mm at Llyn Vyrnwy and 34.8 mm at Gorwel Heights in Llanfairfechan, There were 27 flood alerts in Wales, many roads were flooded including the A4086 in Nant Peris and between Llanwrst and Gwydir Castle that was again flooded (Murlough 15.7C Hawarden 15.7C, Fyvie Castle -0.8C, Capel Curig 74.0 mm, Lerwick 5.1h Wales sunless) [Max 13.4C Min 7.7C Rain 33.6 mm]. Another grey day on the 30th beginning overcast and with slight rain and drizzle visibility was very poor. It had been raining all night, but the wind had suddenly moderated at 0800 GMT and the temperature had fallen two degrees on a cold front and remained steady on 11.3C till 1400 GMT when again it began to fall and from light wind to calm. The afternoon was dry with glimpses of sunshine at times. The minimum temperature was 5.7C at 2000 GMT, thereafter it began to rise reaching 13.3C at midnight (Hereford 17.6C Usk 15.8C, Castlederg 5.5C, Capel Curig 23.0 mm, Leuchars 6.7h Aberporth 0.2h) [Max 15.6C Min 11.2C Rain 3.8 mm]. Pressure had been falling since last evening and on the 31st was 1010 mb at midnight. Storm Aiden, named Met Éireann, 975 mb was steaming N just W of Ireland. At 0900 GMT pressure here 995 mb was falling quickly and the SSE'ly wind was strong to gale force, a gust of 59 mph was recorded at Valley and 50 mph at Gorwel Heights at 0841 GMT. A temperature of 15.6C was recorded at 0752 GMT here in the moist tropical airflow, the maximum of the 30th (09-09 GMT). The temperature had reached 16.5C at Gorwel Heights at 0236 GMT, again the maximum for the 30th. The morning was wet and windy with a maximum temperature of 15.2C occurring just after 0900 GMT, pressure was lowest 993.8 mb at 0938 GMT. With the wind still strengthening a gust of 51 mph was recorded at 1025 GMT as the wind veered SW'ly. At noon the wind started to moderate and the temperature to fall, there were some glimpses of sunshine in the afternoon that was dry (Kinloss 16.5C Capel Curig 15.5C, Redesdale -0.9C Capel Curig 2.8C, Achnagart 60.8 mm Whitechurch 23.8 mm, Kinloss 3.5h Valley 3.2h) [Max 15.2C Min 5.7C Rain 3.0 mm].

    ¤

    The month ended with a rainfall total of 186.3 mm, (159%) & [145%] of averages, the most since 2014 and ranked 12th in Llansadwrn since 1928. A cool moth, the mean temperature 10.8C (-0.6) & [-0.1] of averages, highest since 2018, but ranking 18th lowest in station records since 1979. Sunshine at RAF Valley was 90.6h this was lowest since 2017.

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    November 2020

    November 1 - a fine morning after recent showers of rain. It had been a rough night with gale force winds that had moderated to force 5 WSW'ly at 0900 GMT Gusts of 60 mph had been recorded at Gorwel Heights at 0430 GMT and Gorddinog in Llanfairfechan, and 82 mph at Lake Vyrnwy. All this due to the remnants of tropical storm Zeta. Hurricane Zeta was the record-tying sixth hurricane to make landfall in the United States and the record fifth named storm to strike Louisiana in 2020. Pressure was on 995 mb and began to fall during the morning with low 947 mb S of Iceland and W of Scotland having an occluded front over the Irish Sea and triple point over the Severn estuary. Further gale force winds in the evening with Valley reporting a mws of 45 mph gusting to 56 mph at 2150 GMT with gales from 17 GMT through to midnight. There was moderate to heavy rain from 11 GMT and the temperature rose throughout the day in the moist tropical air reaching 15.0C just before 20 GMT when pressure had fallen to 984 mb and the wind gusting to 50 mph (Hawarden 18.4C Kinbrace 3.4C Capel Curig 56.2 mm Leeming 3.5h Bala 2.2h) [Max 15.0C Min 9.3C Rain 48.6 mm]. At midnight on the 2nd the wind was gusting 42 mph when the temperature fell rapidly and the wind moderated. At 0100 GMT there very heavy rain falling up to 42 mm/h with passage of a cold front, the wind had been all around the compass and began to rise again. At 0900 GMT 48.6 mm of rain was measured as pressure 997 mb was rising quickly. Good misty visibility with light showers and glimpses of sunshine. There was a heavy shower with ice pellets about 1730 GMT (Charsfield 18.0C Cardiff 14.2C Drumnadrochit 4.1C Capel Curig 57.0 mm Yeovilton 6.0h Hawarden 3.9h) [Max 11.2C Min 8.0C Pptn 2.4 mm]. Overnight on the 3rd there had been a few snow pellets to mark the hailometer by morning. Cooler the temperature 6.6C rising after a minimum of 6.1C and 1.3C on the grass. Pressure was on 1014 mb with low 1012 mb central England. Very windy in the SE with gusts of 53 mph reported at Langdon Bay. Pressure was high 1041 mb N of the Azores while complex low 970 mb was at the North Cape. A mostly cloudy day with some weak sunshine and glimpses and slight showers (Cardiff 12.2C Aboyne -1.4C Dunstaffnage 21.2 mm Lyneham 5.9h Hawarden 4.2h) [Max 10.9C Min 6.1C Grass 1.3C Pptn 1.3 mm]. The hailometer was again marked by snow pellets overnight on the 4th with ice precipitation on the highest Snowdonia summits. Snow was lying on Cairngorm, Highlands, at about 40000 ft. Another cool morning 5.0C at 0900 GMT after a minimum of 3.8C and it had been 0.0C on the grass. Frosty in some low lying places and valley bottoms. Pressure 1014 mb was rising with a ridge from Azores high 1045 mb to the SW. Mostly sunny except N Wales and Cumbria coasts where showery with precipitation off the Irish Sea on a NW'ly breeze. Sunny spells and slight showers (Scolton 13.4C, Benson -3.6C Sennybridge -2.1, Achnagart 8.4 mm Capel Curig 3.2 mm, Shoeburyness 8.7h St Athan 8.4h) [Max 10./4C Min 3.4C Grass 0.0C Pptn 0.7 mm], Continuing cool on the 5th with near the normal temperatures for early November. Pressure was 1040 mb with the high centred over St George's Channel. The western fringe was cloudy with mist and fog patches in the SE, it was sunny in the east. Brighter in the afternoon with glimpses of sunshine and spots of rain at times (Aberdeen 16.6C Scolton 13.7C, Exeter -2.7C Pembrey Sands -1.2C, Salsburgh 1.8 mm, Bude 8.2h St Athan 7.4h) [Max 10.1C Min 4.9C Grass 1.3C Rain 0.3 mm]...

    ¤11.5


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