Annual Summary 2025
The weather at Durham in 2025
A very warm, very sunny and dry year
January was a cool month. The mean air temperature was the equal 73rd lowest since 1844. The mean maximum was the equal 94th lowest while the mean minimum was the equal 46th lowest. All three January temperature means were the lowest since 2021. There were no ice days but only 3 days with a mean maximum of 10 °C or above (2 below average). January 5th was the wettest January day on record (33.4 mm), beating the previous record which had stood since 12th January 1921 (32.8 mm). A low-pressure system centred to the south-west of the UK pushed mild, moist Atlantic air into a cold air mass further north. The Met Office reported that the system brought very wet weather to much of Wales, southern, central and eastern England, including to Durham in the north-east. Given such a wet day, it is hardly surprising that the rainfall total for January was above average. However, the month was otherwise generally dry with the number of rain days below average. Given a tendency for clear skies, there were more frosts than usual, and it was a sunny month. Indeed, it was the 4th sunniest January since 1881, although there was more sunshine in both 2023 (98.6 hours) and 2022 (111.6 hours).
February’s weather was dominated by dull, anticyclonic conditions. There were some cold days, including five consecutive sunless days (8th – 12th inclusive) in the middle of the month, but the start and particularly the latter part of the month were mild and sunny. Like January, there were no ice days and there were only 5 air frosts. Mean air temperature was the =41st highest since 1844, but notably cooler than the last three Februarys. The mean maximum temperature was =50th highest and the mean minimum temperature was =40th highest. It was the 85th driest February in 176 years with less than 75% of the usual amount. With just 4 hours more sunshine than February 2024, this was the 70th dullest February on record, perhaps not surprising given 5 days with no sunshine and a total of only 3.3 hours of sunshine between the 7th and 18th inclusive. Winds in this period were from the ‘easterly’ quadrant, between NE and SE, bringing much cloud cover off the North Sea. This was also a period with a very low temperature range: maximum temperatures averaged just 4.3 °C yet minimum temperatures averaged 1.3 °C.
Overall, it was a mild winter. The mean maximum temperature (7.9 °C, +0.7 °C above average) was the =16th highest since 1844, and the mean minimum temperature ((2.0 °C, 0.6 °C above average) was the =19th highest; the mean air temperature (5.0 °C, 0.7 °C above average) was also the =19th highest on record. Rainfall (146.2 mm) was a little below average (92%). The amount of sunshine this winter (197.2 hours) was just below average; it was, nevertheless, the 30th sunniest winter since 1881 but nowhere nearly as sunny as 2023 (249.7 hours) or 2022 (253 hours).
Although there were some cool days in the middle of March, mostly the days were mild, yet the nights were cold. There was the 9th highest mean maximum temperature, yet the mean minimum was only the 46th highest in 182 years. Overall, there was the 13th equal highest mean air temperature for March since 1844. There were 22 days with a maximum above 10 °C, 6 above average. In relation to the relatively cold nights, there was only the 49th highest mean grass minimum since 1874, with 19 ground frosts, 5 above average. It was the equal 33rd driest March on record, the driest March since 2020. All three long-term rainfall totals are now below average. Most notably, it was a very sunny month, the 5th sunniest March on record at Durham since 1881. There was 11.4 hours of sunshine on the 26th, the 5th equal sunniest March day on record, the sunniest March day this century. In a month dominated by anticyclonic conditions, the pressure never fell below 999.9 mbar.
April was an exceptional month although only one record was broken: there was the warmest April day on record on the 30th (24.4 °C). It was the 3rd hottest April on record (9.9 °C) since records began in 1844, surpassed only in 2007 (10.7 °C) and 2011 (11.2 °C). There was the 4th highest mean maximum and the 11th highest mean minimum. 29 days had a maximum above 10 °C, 6 more than average. The daily range on the 10th was 20.2 °C, the 41st highest daily range since 1850 and the second highest in April – 21.0 °C on 12th April 1906. The highest daily temperature range at Durham was 23.7 °C on 5th August 1916. It was the 4th driest April on record since 1850. There was the equal 2nd lowest number of rain days. It was the 3rd sunniest April on record (since 1882); only 2021 (229.5 hours) and 1914 (238.1 hours) have had sunnier Aprils in Durham.
This was the 8th warmest May on record (12.33 °C, 1.3 °C above average), marginally warmer than May 2023 but a little cooler than May 2022 and the warmest May on record, 2024 (13.59 °C). Thus, the 2020s have experienced some remarkably warm late-spring weather. Of the ten warmest Mays on record at Durham, five have been in the 2020s! The warmest day was the 1st (25.6 °C), the warmest May Day on record and the 9th warmest of any days in May. The lowest maximum was 11.0 °C on the 5th whereas the highest minimum was 13.7 °C on the 30th. Given the hot, sunny weather, it is no surprise that the mean concrete minimum was well above the mean grass minimum. Unlike last year when May was wet, this May was quite dry, the 28th driest on record. Only ten Mays have had fewer rain days since 1850; there were just three in 1859, the driest May on record. There was an absolute drought (15 days or more with no rainfall) from the 6th to the 21st inclusive (16 days). This was the 7th sunniest May on record, the sunniest since 2020. There was some measurable sunshine every day. In a month dominated by anticyclonic weather, of the first 23 days, 21 had winds from the NE quadrant at 0900.
Spring was the 3rd warmest on record (9.80 °C); only 2004 (9.86 °C) and 2017 (9.85 °C) have had warmer springs. This was also the 3rd driest spring on record (48.2 mm); only the springs of 2020 (42.4 mm) and 1956 (45.3 mm) have been drier. The 2025 spring saw just 35% of the normal rainfall, 88.8 mm less than expected. This counts as a drought, where a drought is defined as a period of 3 months with at least a 50% rainfall deficit; in this case the deficit was 65%. There were just 26 rain days this spring, the equal 4th lowest total on record, 18 fewer rain days than in a normal spring. It was by some margin the sunniest spring on record (since 1882); the May 2025 total (650.5 hours; more than 50% of the possible total) easily surpassed the previous record holder (2020: 630.3 hours). The results suggest that one manifestation of climate change at Durham is a tendency for warmer, drier, sunnier springs with May more like a traditional summer month than the end of spring.
This was the 2nd hottest June on record at Durham since 1844, surpassed only by the exceptional June of 1846 (17.5 °C); certainly, this is the hottest June on record since the introduction of a Stevenson screen in 1899*. The mean maximum temperature is 3rd equal highest (with 2023), and the mean minimum is the 2nd highest after 1846. The absolute maximum of 29.1 °C on the 30th is the 7th hottest June day on record, the hottest June day since 6th June 1989. Perhaps most remarkable were two extremely warm nights: the minimum on the 21st (17.7 °C) is the 2nd warmest June night on record, whilst the minimum of 17.3 °C on the 28th is the 5th warmest. Not surprisingly, the mean grass minimum temperature is the equal highest on record for June (with 2017). June was a relatively dry month, the 66th driest June in 175 years. There were 16 rain days, 1 above average. Long-period totals remain well below average. It was another very sunny month, the 20th sunniest at Durham since records began in 1882. It was the sunniest first half of any year since 1881 with 1024.6 hours compared to the previous record: 955.3 hours in 2020. It has been the 7th driest first half of the year since 1850 (178.6 mm), the driest since 1949 (142.6 mm), the second driest on record. The driest January-June was 1858 with just 123.1 mm. It has been the 8th warmest first half of a year since 1844 (8.91 °C). All the warmer years have been this century, with the warmest 2004 (9.14 °C) followed by last year, 2024 (9.12 °C). [The accuracy of early temperature measurements at Durham is discussed at some length in Burt & Burt: Appendix 3, Durham weather and climate since 1841, OUP, 2022.]
Whilst not as exceptional as June, this was still a very warm July, the 6th hottest at Durham since 1844, the warmest July since 2022 (17.9 °C). Both the mean maximum and the mean minimum air temperatures were 8th highest on record. There was a heat wave for four days (10th-13th inclusive), the first since 2022. The hottest day was the 11th (27.8 °C); 43 days in July have been hotter since 1850. Rainfall was a little below average. All months so far this year have had below-average rainfall except January, and all the long-term totals remain well below average. The wettest day was the 19th (13.6 mm), only the 4th day this year to have a total above 10 mm. Sunshine was very close to average for the month.
With a mean air temperature of 17.17 °C, this was the 5th hottest August at Durham since 1843; only 1947 (17.20 °C), 1975 (17.24 °C), 2022 (17.30 °C) and 1995 (17.59 °C) have been hotter. The 13th was the third hottest August day at Durham since 1843; only two August days in 1990 were hotter (2nd: 31.9 °C, 3rd: 32.5 °C). The second heatwave of the Durham summer happened from the 12th to the 15th inclusive (all days with a maximum of at least 25 °C). It was the 14th driest August at Durham since 1868, the driest since 2022 (13 mm). It was another sunny month, 29th sunniest in 145 years of record.
This has been the hottest summer on record since 1844 at Durham: 16.92 °C, surpassing the previous record of 16.67 °C set in 2022. Based on the Eglise extension, one summer may have been even hotter than this one: 1826 (17.3 °C). The mean maximum temperature was the highest on record (21.85 °C), beating the previous 2022 record (21.63 °C), so too was the mean minimum (12.48 °C), beating the previous record from 2003 (11.97 °C) with 2022 close behind in third place (11.80 °C). As noted above, 13th August was a notably hot summer’s day, the equal 8th hottest summer day at Durham, but not close to the 19th July 2022 record holder (36.9 °C). There were two heatwaves, one in mid-July and one in mid-August. It was a dry summer (111.2 mm), the 20th driest since 1850. Not surprisingly, it was also a sunny summer (566.5 hours), the 22nd sunniest in 143 years. Using the Davis optimum summer weather index, 2025 ranks as the 4th best summer overall (806) at Durham since 1900, behind 2022 (809), 1995 (813) and 1976 (831).
For the first time since January, we had a month with its mean air temperature below the 1991-2020 average, albeit by only a tiny amount. Even so, this was the equal 51st warmest September in Durham since 1843, confirming the occurrence of global warming in recent decades. This mean air temperature is therefore just outside the upper quartile. It was warmer than September 2024. Days were a little above average but nights below average. Rainfall was above average for the month. The fall of 32.4 mm on the 20th was the 13th wettest September day since 1850, resulting from an active cold front moving slowly across northern England. Rainfall fell for 16 consecutive hours with a maximum hourly intensity of 4.4 mm per hour (17:00 – 18:00). September was the first month this year when the number of wet days exceeded the average. Despite above-average rainfall, it was the 30th sunniest September in 143 years.
As usual in October, temperatures fell as the month wore on, but the rate of cooling was not dramatic, and this ended up the 19th warmest October since 1850. The mean maximum was the 30th highest and the mean minimum was the 16th highest. Relatively warm nights are confirmed by the 12th highest mean grass minimum since 1874. There were no air frosts and only one ground frost, on the 30th. It was the =69th driest October since 1850 but also the 49th dullest October in 145 years.
November started very mild with a maximum of 16 °C on the 4th, the 19th equal warmest November day since 1900. Some much colder days were experienced in the third quarter of the month with a maximum of only 2.5 °C on the 19th. An incursion of much milder air late on the 26th meant that the maximum temperature allocated to the 26th (12.8 °C) was actually measured at 0900 on the 27th! – a rare example of a maximum temperature not being recorded in the middle of the day. The temperature was -1.6 °C at 08:00 on the 26th, and 1.7 °C at 10:00. By 22:00 air temperature had risen to 5.8 °C but was up to 11.1 °C by 02:00 on the 27th! Overall, mean air temperature was 7.5 °C in November, the equal 16th warmest November since 1850. Nights were notably milder than normal, and both the numbers of ground frosts and air frosts were average for the month. It was the wettest month since October 2023, the sixth wettest November on record since 1850 and the wettest November since 2009. The 3- and 6-month running totals are now above average, but the 12-month running total remains below average. The fall of 29.4 mm on the 12th is the 17th wettest November day on record. Surprisingly, the monthly sunshine total was only just below average. Despite being such a wet month, there was only one day with no recorded sunshine, although 11 days only recorded one tenth (6 minutes) of an hour’s sunshine!
The mean air temperature for autumn as a whole was 10.5 °C, 0.5 °C above average, the 14th warmest autumn on record. Autumn rainfall totalled 261.8 mm,135% of average, the 20th wettest autumn on record. Even so, the autumn sunshine total was almost exactly average (298.6 hours).
The mean air temperature of 6.30 °C was the 10th highest for December on record (since 1843). The mean maximum air temperature was the =17th highest and the mean minimum air temperature was the =9th highest. This reflected some very mild days in the first half of the month and a lack of very cold nights. The absolute minimum would have been very high for December had it not been for the sharp frost on the 31st; even so, -2.6 °C is the =32nd highest absolute minimum for any December in 176 years. There was the =2nd lowest number of air frosts (since 1900) and the 8th lowest number of ground frosts (since 1874). December’s rainfall total was close to average with fewer hours of bright sunshine than normal.
2025 was the second warmest year on record at Durham since 1850 (10.49 °C), exceeded only in 2022 (10.59 °C). The last four years have been the four warmest on record, a remarkable sequence of very warm years. There were 37 air frosts, the equal 11th lowest total on record. There were 85 ground frosts, the 16th lowest total, over half occurring in the first three months of the year. It was the 45th driest year since 1850 (580.4 mm), the driest year since 2011. It was also the sunniest year on record (1722.1 hours) since 1881.