January 2024Wet with some wintry weather mid month near average temperatures overallMild at the beginning a wintry spell in the middle with a wet and mild end Rainfall was 172.2 mm (142%) & [167%] of averages, most since 2021 ranking 9th out of 96 Llansadwrn records. The wettest day was on the 23rd having 23.6 mm. Six days (+2.2) had no precipitation what so ever and there were 8 dry days (defined as having <0.2 mm). Rain days (>= 0.2 mm) were 23 (0.5); wet days (>=1.0 mm) were 10 (+2.4); and days having 5 mm, or more. totaled 11 (+2.8). It was wetter in Llanfairfechan at Gorwel Heights where 194.8 mm fell, most since 2021, the second largest on record since 2011 at the station. The wettest days were on the 29th when 29.2 mm fell and 28th when 27.2 mm fell. There were 9 dry days; 22 rain days; 20 wet days; and 12 had 5 mm, or more. There were 165 wet hours duration with an average fall of 1.2 mm/h. With the same rate of rainfall 1.2 mm/h Llansadwrn had 147 wet hours duration. The mean temperature in Llansadwrn was 5.7C (0.0) & [+0.3] of records, lowest since 2021, ranking 17th highest in station records since 1979. The mean maximum was 7.9C (0.1) & [0.0] the highest maximum 12.7C (+0.6) on the 28th and the lowest 3.7C (0.7) on the 9th. The mean minimum was 3.5C (+0.2) & [+0.6], there were 2 days (1.4) with air frost lowest 2.6C on the 18th and 2.3C on the 19th, frost duration was 31.8h . Ground frost occurred on 12 days (5.1) the lowest 6.0C was on the 18th. At Gorwel Heights the mean temperature was 6.5C lowest since 2021 and the 3rd lowest in records since 2021. The highest mean 12.1C was on the 28th and the lowest 2.2C on the 17th. The mean maximum was 8.6C with the highest maximum 17.8C on the 28th a station record for January, the lowest 2.8C on the 17th. The mean minimum was 4.3C and there were 2 days with a touch of air frost 0.6C on the 18th and 0.4C on the 19th of just 5.2h duration.
February 2024Above average temperatures and rainfall, less sunshine than usualMildest and sunniest in the middle of the month A very mild month with the mean temperature 7.6C (+1.4) & [+2.0] of averages, highest since 2019 ranking 3rd in station records since 1979. The mean maximum 10.0C (+1.2) & [+1.6] highest since 2019, the highest maximum 12.8C on the 14th with the lowest 5.8C on the 8th (+1.4). The mean minimum 5.1C (+1.6) & [+2.3] of averages ranked 2nd, highest since 1998. The highest minimum was 10.1C on the 15th and the lowest 0.9C on the 25th, there were no air frosts, the last February with air frosts was in 2021 that had six. There were 9 ground frosts with the lowest 5.6C on the 9th, least since 2011 (there were 23 in 2018 and the most in recent years 24 in 1986). At Gorwel Heights, Llanfairfechan, the mean temperature was 8.7C (+1.8) & [+2.6] was highest on record. The mean maximum was 11.1C, highest since 2019 R2, the highest maximum 15.8C on the 15th and the lowest 5.3C on the 8th. The mean minimum was 6.3C highest on record, the highest 11.0C on the 15th and the lowest 2.3C on the 25th highest since 2022 R2. Rainfall in Llansadwrn was 134.3 mm (122%) & [148%] of averages, most since 2021 ranking 13th in records back to 1928. Most rainfall in a day was on the 28th with 20.3 mm There was just one day with no precipitation recorded and 4 (4.8) dry days; 25 (+5.6) rain days; 19 (+5.6) wet days; and 8 (+1.0) days had 5 mm, or more. Rainfall duration was 152h. At Gorwel Heights rainfall was 147.4 mm (161%) & [197%] of averages, most since 2020 R2. The wettest day was on the 8th having 33.2 mm, 6 days had 10 mm or more. There were 9 dry days; 20 rain days; 17 wet days; and 9 had 5 mm, or more. Sunshine at RAF Valley was a provisional 69.5h, least since 2017 R32. The sunniest day was on the 26th with 7.5h, there were 10 sunless days.
Winter 2023/24Warmer and wetter than 30y climatological averages. Wetter the last decade, but average on temperatures.
March 2024An atypical month. Wet with below average sunshine and above average temperaturesSimilar throughout. Temperatures continue to be above normal with the mean 8.0C (+0.9) & [+1.0} of averages highest since 2022 ranking 8th in station records since 1979. The mean maximum 11.0C ranked 15th with the highest maximum 14.9C reached only on the last day the 31st (1.4). The lowest maximum 6.3C in the 1st was (+1.5). Minimum temperatures were most significantly above the averages with the mean 5.1C (+1.2) & [+1.3], the lowest 1.0C on the 2nd (+1.6). There were no air frosts and only 7 ground frosts (7.3) mostly at the beginning of the month, lowest 2.6 (+2.4). At Gorwel Heights in Llanfairfechan the mean temperature was 8.8C (+1.0) & [+1.2] of averages equal highest with 2019 on record since 2011. The highest maximum was 15.9C on the 14th that also had the highest minimum 11.0C. The mean minimum was 6.1C equal highest with 2022 since 2017 with 6.2C ranking 3rd in records. The lowest minimum on the 2nd was 0.8C highest since 2022. A wet month with rainfall of 131.1 mm in Llansadwrn (131%) & [167%] of averages and 123.6 mm (130%) & [149%] of averages at Gorwel Heights. The wettest day was on the 13th with 29.8 mm in Llansadwrn and 27.2 mm at Gorwel Heights. In Llansadwrn there were 5 days (2.9) with no precipitation recorded and 9 dry days (3.2). Rain days were 22 (+3.2); wet days 18 (+4.0) and 8 days (+1.8) had 5 mm, or more. At Gorwel Heights there were 9 dry days; 22 rain days; 19 wet days; and 8 had 5 mm, or more. Rainfall duration (wet hours) in Llansadwrn 145h and Gorwel Heights 119h. Sunshine at RAF Valley was 114.1h (provisional) with the sunniest day on the 30th having 10.1h and 2 sunless days. Cloudier in Llansadwrn where there were 6 sunless days.
April 2024A wet month, but driest since 2019. Temperatures above average, sometimes windy. Sunshine below average.Wet and windy at the beginning, drier and brighter towards the endRainfall was 91.0 mm, not reaching 100 mm that eight Aprils have had in Llansadwrn since 1928, largest since 2012 ranking 15th. This was [129%] of the 30y average, but (201%) of the last decade reflecting drier Aprils in recent years. The largest fall was a modest 14.6 mm on the 8th and 6 days (8.1) had no precipitation. Dry days numbered 10 (6.8); rain days were 20 (+6.8); wet days 16 (+6.8); and there were 7 days (+3.5) with 5 mm, or more. At Gorwel Heights in Llanfairfechan rainfall was 97.6 mm largest since 2018, the wettest day was on the 5th with 21.2 mm and the 8th with 20.0 mm not far behind. These were the only two days to exceed 10 mm and made up 42% of the month's total. There were 8 dry days; 22 raindays; 14 wet days; and 7 reached 5 mm, or more. Rainfall duration (wet hours) was 112 h and in Llansadwrn 125h. Temperatures were above the average, particularly the minima while the maxima struggled to reach the normal. In Llansadwrn the mean was 9.7C highest since 2020 ranking 10th highest in station records, (+0.3) & [+0.6] of averages. The mean minimum was 6.6C (+0.9) & [+1.0] of averages, the highest was 11.4C on the 6th (+1.6) and lowest 2.6C on the 26th (+1.5). The mean maximum 12.9C, (0.4) & [+0.1] of averages, lowest since 2021 ranked 22nd warmest in records since 1979, the highest maximum 18.9C on the 5th was (1.3), the lowest maximum 2.8C on the 26th was (+1.4). The was no air frost and just 3 days (4.1) of ground frost, lowest 0.7C on the 10th. At Gorwel Heights the mean temperature was 10.1C (+0.5) & [+0.5] of averages, highest equal with 2022 since 2020. The highest mean was on the 11th with 15.0C and the lowest 6.5C on the 26th. The mean maximum was 12.9C, lowest since 2021, the highest 20.7C on the 5th and the lowest 9.3C on the 26th. The mean minimum was 7.2C, the highest 12.6C on the 6th and lowest 3.6C on the 26th Sunshine at RAF Valley was a provisional 138.0h, lowest since 2019. The sunniest day was on the 20th having 12.8h, 5 days had 10h, or more,and there were 2 sunless days. Rainfall was 82.8 mm.
May 2024The warmest May and Spring on record, but dull and wetDriest with highest temperatures in the first half, wet and cooler in the second half The mean temperature 14.0C was the highest in May at this station since records began in 1979 and a huge (+1.9) & [+2.2] of averages. The mean minimum 10.4C, highest since before 1979 reaching double figures for the first time with even larger anomalies (+2.1) & [+2.5]. The mean maximum 17.5C was highest since 1992 and ranked fourth highest in records. The highest maximum on the 11th was 25.4C (+3.8), not unusual for May, was equal highest with 2020 since 2017. Five days reached, or exceeded 20C. The lowest maximum was 10.6C on the 23rd. The highest minimum was 14.5C on the 12th while the lowest 6.3C was on the 1st. There were no ground frosts. At Gorwel Heights the mean temperature 14.0C was highest on record since 2011. The mean maximum was 17.2C with the highest maximum 25.2C on the 11th and the lowest 10.9C on the 23rd. The mean minimum was 10.8C and highest on record though reaching double figures twice in the past in May. The lowest minimum was 7.6C on the 25th. The graphic left, shows anomalies from the 30year May mean of 11.8C, computed using a comparatively extended data series back to 1942, from 1978 using Valley observations. Llansadwrn onsite data are used from 1979. The 2024 exceeds the previous greatest anomaly in 2008 13.6C by 0.4C
May was wetter than usual with 87.6 mm recorded in Llansadwrn (124%) & [129%] of averages, largest since 2021 ranking 21 since 1928. The largest fall was on the 22nd with 22.4 mm. There was a week (511th) of dry weather at the beginning of the month and overall there were 14 days without precipitation. There was 17 dry days; 14 rain days; 11 wet days; and 9 days had 5 mm, or more. Rain duration was 101h (wet hours). It was wetter at Gorwel Heights with a not unusual 117.6 mm of rain. The wettest day was on the 22nd when 37.6 mm fell. Dry days numbered 18; rain days 13; wet days were 12; and 9 reached 5 mm, or more. Rain duration (wet hours) here was 106 h. It was a dull month. Sunshine at RAF Valley was 172.4h (provisional) least since 2014, (76%) & [85%] of averages. The sunniest day with 12.8h sunshine was on the 11th and there ware 5 sunless days. .Spring 2024Warm and wet. Rainfall largest since 2021, ranked fourth highest in Llansadwrn records back to 1928.
It was the warmest spring on record since 1979 when observations began in Llansadwrn.
It was the fourth largest spring rainfall in the Llansadwrn record beginning 1928.
June 2024Cool. drier than usual and fairly sunnyAn unsettled month with a few warm sunny days and some dull wet daysTemperatures were below averages for the first time this year and had greater anomalies since May 2021. Greatest anomalies were with the decadal averages less so with the 30y averages. The mean 12.6C (1.3) & [0.5] of averages was equal lowest since 2014. The mean maximum 17.1C (1.5) & [0.6] was equal lowest since 1012 ranking 14th lowest in station records since 1979. The highest maximum 25.6C was on the 26th and the lowest 13.6C on the 9th. The mean minimum 10.0C (1.3) & [0.5] was lowest since 2015 ranking 22nd lowest. The lowest grass minimum 4.1C on the 5th a rare (+0.5) of average. Temperatures at Gorwel heights, Llanfairfechan, were similarly below average. The mean 14.3C equal lowest since 2011 when records began was (1.4) & [0.6] of averages. The mean maximum 17.7C was lowest since 2012 with the highest 26.2C on the 26th and the lowest 13.9C on the 9th. The mean minimum 10.9C was equal lowest with 2021. The highest was 14.5C on the 23rd and lowest 7.3C on the 5th. Rainfall was blow average, but was characterised by long spells of slight rain and drizzle particularly in Llansadwrn when the island was enveloped in low cloud/ fog. The wet hour duration values were 94h in Llansadwrn and 50h at Gorwel Heights. Rainfall totals were not dissimilar and most since 2020, 48.9 mm in Llansadwrn, ranking 32 lowest since 1928 and 46.4 mm at Gorwel Heights. Greatest falls were 11.8 mm on the 9th in Llansadwrn and 19.8 mm on the 9th at Gorwel Heights. In Llansadwrn there were 5 days with no precipitation (7.3); 10 dry days (5.9); 20 rain days (+5.9); 14 wet days (+3.9); and 3 days (1.4) had 5 mm, or more. At Gorwel Heights there were 15 dry days; 15 rain days; 7 wet days; and 3 days had 5 mm, or more. Sunshine at RAF Valley 215.1h (provisonal) was [115%] of the 30y climatological average, but (97%) of the last decade's average, ranking H21st on the Anglesey record back to 1931. The sunniest day was on the 24th having 13.4h and there were 2 sunless days.
July 2023A month of below average temperatures with more rainfall and less sunshine than usualWetter at the beginning, a few sunny warm days and a drier endCoolest since 2020 with the mean temperature 15.2 (0.9) & [0.6] of averages. The mean maximum was 18.7C (1.0) & [0.6] of averages with the highest maximum 24.1C on the 29th (4.0) and lowest 14.7C on the 11th (0.4). The mean minimum was 11.8C (0.8) & [0.5] with the lowest 7.8C (1.3) on the 8th that also had the lowest grass minimum of 4.2C (1.3). At Gorwel Heights, Llanfairfechan, the mean temperature also lowest since 2020 was 15.9C (1.1) & [0.8] of averages with the highest 24.2C on the 19th and lowest 14.8C on the 11th. Gorddinog recorded 24.9C on the 19th. The mean minimum was 12.5C with the lowest 8.7C on the 8th. Rainfall was above average with 102.4 mm (114%) & [132%] of averages falling in Llansadwrn least since 2022 ranking 24th largest in records since 1928. The largest fall 17.8 mm was on the 5th, but 13.0 mm fell next day on the 6th. There was a dry spell of 5days at the end of the month (2630th). Days with no precipitation numbered 8 (1.5) and there were 12 dry days (1.1). Rain days were 19, wet days 15, and 7 days had 5 mm, or more. Rain fall duration (wet hours) was 120 h. It was wetter at Gorwel Heights where 148.4 mm fell (161%) & [186%] of averages. The largest fall 35.4 mm on the 22nd was second largest on record less than the 47.4 mm recorded in July 2012. There were 10 dry days; 21 rain days; 13 wet days; and 9 had 5 mm, or more. Rainfall duration (wet hours) was 101 h. Rainfal;l at Gorddinog was 96.5 mm with the largest fall 17.3 mm on the 11th. It was a rather dull month particularly in Llansadwrn with 7 sunless days. Sunshine at RAF Valley was 96.5h (provisional) (85%) & [94%] of averages. The sunniest day was on the 28th with 14.0h, there were 3 sunless days..
August 2024Close to average rainfall, significantly drier in Llanfairfechan. Temperatures and sunshine above averagesA mixed month, some sunny and warm days interspersed with very dull and wet days.Rainfall was 86.4 mm (88%) & [96%] of averages, largest since 2022 ranking 46 least since 1928. The largest fall was 14.8 mm on the 5th. There were 9 (+1.6) days with no precipitation; 14 (+1.3) dry days; 17 (1.3) rain days; 12 (1.2) wet days; and 7 days (+2.0) had 5 mm, or more. Rainfall duration (wet hours) was 92 h. Gorwel Heights had 46.0 mm (43%) & [52%] of averages, the driest recorded here since records began in 2011. Gorddinog was drier reporting 41.0 mm. The wettest day at Gorwel was the 22nd with 10.4 mm when Gorddinog had 7.3 mm. At Gorwel there were 13 dry days; 18 rain days; 10 wet days; and 4 reached 5 mm, or more. Rainfall duration was 80 h. Temperatures were above averages. At Llansadwrn the mean was 16.1C (+0.3) & [+0.5] and at Gorwel Heights 17.5C (+0.8) & [0.9] of averages. Highest were 26.1C in Llansadwrn on the 11th and 27.3C at Gorwel Heights Sunshine at RAF Valley was 189.6h (MetO provisional) most since 2022 and despite 6 sunless days ranked 11th highest in Anglesey records since 1931. The sunniest day was on the 31st having 12.1h. Summer 2024It was the coolest summer since 2015. It was the driest summer since 2022, close to the averages rank 46 largest rainfall since 1928 in Llansadwrn, but driest in Llanfairfechan Gorwel since before 2011.
September 2024Wettest September since 1976, a station record (since 1979). Temperatures a little below averages.Some very wet days throughout, cooler days with thunder and hail towards the middle Rainfall 178.3 mm, (173%) & [176%] of averages, was a station record for September and largest in Llansadwrn records since 1957, rank 6th largest since 1928. The wettest day was on the 1st with 54.4 mm falling and the last two combined had 44.2 mm. There were 146 wet hours duration with an average 1.3 mm falling per hour. It was not all wet, however, as 8 days (1.1) had no precipitation and there were 14 dry days (+4.9). Rain days were 16 (1.4) and near average wet days 13 (+0.3) while 8 days had 5 mm, or more. The month's rain brought the total for the year (right) up to 1032.2 mm, most since 2020 and third largest in Llansadwrn records since 1928. Wettest was 1957 having 1068.7 mm accumulated by the end of September.
Gorwel Heights was wetter having 204.8 mm (196%) & [214%] of averages, least since 2023 that had 216.4 mm. The largest fall of 35.8 mm was on the 1st while 28.6 mm fell on the 26th and the last two days 12.4 mm and 31.8 mm. here there were 9 dry days; 21 rain days; 17 wet days; and 11 had 5 mm, or more. The mean temperature in Llansadwrn was 13.8C (0.76) & [0.2] of averages, lowest since 2018 and ranking 22nd highest since 1979. The maxima had the largest negative anomalies with the mean (1.1) & [0.5] with the highest maximum 23.4C on the 7th and the lowest 12.3C on the 30th. The mean minimum was 10.9C (0.4) & [+0.2] of averages, the lowest minimum was 5.9C on the 28th while the lowest grass minimum was 2.6C on the 28th. At Gorwel Heights the mean minimum was 14.3C (1.0) & [0.6] of averages, lowest since 2018. The mean maximum was 16.7C with the highest 22.7C on the 19th and lowest 12.5C on the 30th. The mean minimum was 11.7C with the highest 17.4C on the 7th and lowest 7.4C on the 13th. Thunder was heard on the 11th at 1227 GMT, just before at 1212 GMT there had been a shower of 23 mm ice pellets. Ice pellets fell also on the 12th and 15th the three occasions in the month more than usual (+2.4). Sunshine at RAF Valley was 142.5h (provisional), the sunniest day on the 17th had 11.5h and there were 5 sunless days.
October 2024Drier than usual and rarely <100 mm, temperatures a bit above averages.Above average sunshine at the beginning, very dull with large number of sunless days at the end. Total rainfall was 91.8 mm (62%) & [71%] of averages, least since 2016, and one of the 30 drier Octobers on the Llansadwrn record since 1928. There have been 63 Octobers that have returned more than 100 mm, highest this station 282.8 mm in 2008 and lowest 37.9 in 2016. Lowest on the Llansadwrn record was in 1946 with 8.6 mm (at Gadlys Cottage) and 17.3 mm (at Treffos). The wettest day was on the 27th with 21.0 mm, but 16.0 mm fell on the 16th. There were 7 days (+0.8) with no precipitation; 12 (+2.3) dry days; 19 (2.1) rain days; 14 (2.2) wet days; and 7 (1.3) days had 5 mm, or more. Rainfall at Gorwel Heights was 94.6 mm (64%) & [75%] of averages the most 13.6 mm falling on the 25th. There were 14 dry days; 17 rain days; 13 wet days; and 9 days had 5 mm, or more. Rainfall duration (wet hours) was 95h while Llansadwrn recorded 91h. The monthly mean temperature in Llansadwrn was 12.0C (+0.3) & [+0.9] of averages, lowest since 2020 ranking 13th highest since 1979. The mean maximum was 14.9C with the highest 18.3C on the 5th (1.3) and the lowest 10.4C on the 13th (0.4). The mean minimum was 9.0C with the lowest 3.5C on the 13th. There were no ground frosts the temperature on the grass falling to 0.0C on the 11th and 13th. At Gorwel Heights the mean temperature was 12.7C (+0.3) & [+0.8] of averages. The mean maximum was 15.4C with the highest 19.4C on the 7th and the lowest 10.6C on the 10th. The mean minimum was 10.0C with the highest 13.5C on the 25th and lowest 5.4C on the 11th. Overall it was a sunny month especially at RAF Valley where 104.9h were recorded, sunniest since 2022 (provisional). The sunniest day was on the 14th with 9.5h. There were just 3 sunless days, but in Llansadwrn there were 9 with some very dark 'lights on' days especially the 25th and 30th when solar radiation values 1.24 MJ m ^{2} and 1.79 MJ m ^{2} respectively were recorded.
Monthly data 2024
Llanfairfechan, Gorwel Heights observations
AcknowledgementsThe Met Office at RAF Valley kindly supplied observational data from 1942 to 2011. Current data (provisional) are gathered from SYNOP reports and METAR, final data from the Met Office website. I am grateful to David Lee for use of data from Gorddinog.
