June 2025
SUMMARY OF THE METEOROLOGICAL READINGS AT DURHAM UNIVERSITY OBSERVATORY
June 2025
Temperatures (all temperatures in degrees Celsuis; all averages 1991-2020)
Mean daily maximum: 20.7 Difference from average: +2.7
Mean daily minimum: 11.6 Difference from average: +2.3
Mean air temperature: 16.2 Difference from average: +2.5
Absolute maximum: 29.1 (30th)
Absolute minimum: 6.4 (4th)
Mean grass minimum: 9.9 Difference from average: +2.3
Absolute grass minimum: 3.9 (7th)
Mean concrete minimum: 12.0
Absolute concrete minimum: 6.5 (4th)
Number of ground frosts: 0 Difference from average: 0
Number of air frosts: 0 Difference from average: 0
Mean soil temperature at 300 mm depth: 16.6
Mean soil temperature at 1000 mm depth: 14.5
Rainfall (all totals in millimetres; all averages 1991-2020)
Total for the month: 36.0 Difference from average: -25.2
Percentage of the average: 59%
Wettest day: 11.2 (7th)
Number of rain days (>0.1 mm): 16 Difference from average: +1
Number of wet days (=>1.0 mm): 9
3-month total rainfall to 30th June 2025: 63.4 Difference from average: -93.5
6-month total rainfall to 30th June 2025: 178.6 Difference from average: -117.9
12-month total rainfall to 30th June 2025: 510.6 Difference from average: -170.4
Sunshine (all totals in hours; all averages 1991-2020)
Total for the month: 215.3 Difference from average: +50.
Percentage of the average: 131%
Mean daily sunshine: 7.2 Difference from average: +1.7
Sunniest day: 11.6 (29th) Number of days with no recorded sunshine: 0
Note that the monthly sunshine total is now calculated from the UKMO E&NE regional total. Daily sunshine totals quoted here and in the data summary are uncorrected.
Wind (kph; all data from the West Building roof, Lower Mountjoy campus)
Average wind speed: 1.9
Maximum gust: 17.9 (27th, 15:15, W)
Pressure (mbar)
Average: 1012.1
Maximum: 1026.6 Minimum: 995.2
Comments on June 2025
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 has easily been 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.]
Emeritus Professor Tim Burt
Department of Geography
Durham University