SUMMARY OF THE METEOROLOGICAL READINGS AT DURHAM UNIVERSITY OBSERVATORY
Temperatures (all temperatures in degrees Celsuis; all averages 1991-2020)
Mean daily maximum: 22.5 Difference from average: +2.3
Mean daily minimum: 13.3 Difference from average: +2.0
Mean air temperature: 17.9 Difference from average: +2.1
Absolute maximum: 36.9 (19th)
Absolute minimum: 9.0 (16th)
Mean grass minimum: 12.0 Difference from average: +2.5
Absolute grass minimum: 6.4 (5th)
Mean concrete minimum: 14.2
Absolute concrete minimum: 9.2 (5th)
Number of ground frosts: 0 Difference from average: 0
Number of air frosts: 0 Difference from average:
Mean soil temperature at 300 mm depth: 18.5
Mean soil temperature at 1000 mm depth: 16.2
Rainfall (all totals in millimetres; all averages 1991-2020)
Total for the month: 49.2 Difference from average: -12.8
Percentage of the average: 79%
Wettest day: 16.4 (30th)
Number of rain days (>0.1 mm): 14
Number of wet days (=>1.0 mm): 12
3-month total rainfall to 31st July 2022: 139.4 Difference from average: -20.1
6-month total rainfall to 31st July 2022: 272.0 Difference from average: -82.7
12-month total rainfall to 31st July 2022: 582.2 Difference from average: -99.8
Sunshine (all totals in hours; all averages 1991-2020)
Total for the month: 180.9 Difference from average: +5.7
Percentage of the average: 103%
Mean daily sunshine: 5.8 Difference from average: +0.2
Sunniest day: 10.4 (10th)
Number of days with no recorded sunshine: 2
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: 5.2
Maximum gust: 57.9 (6th, 13:15, SW)
Comments on July 2022 – a record-breaking month!
The maximum temperature at Durham Observatory on 19th July was 36.9 °C, a full 4 degrees higher than the previous record set on 25 July 2019. Usually, records are broken by just a few decimal points, so this is an astonishing difference! Stephen Burt and I have learned that, as soon as you publish a book about weather and climate, records are bound to be broken; so, our book on Durham weather and climate since 1841 published by OUP in May is therefore out of date already! The minimum temperature on the morning of the 20th was 17.7 °C, the 5th highest on record for any month, but there had already been two higher minima this month, including 18.4 °C on the 12th, the second highest on record, and 18.1 °C on the 18th, the 3rd equal highest. Not surprisingly, 19th July 2022 is easily the warmest day on record at Durham (mean air temperature: 27.2 °C, the average of the days’ maximum and minimum temperatures; the average of the hourly means was 27.0 °C) with the day before the second warmest (25.1 °C), both surpassing the previous record of 24.4 °C on 3rd August 1990. There were 4 days in a row with maxima above 25 °C, thus constituting a ‘heatwave’ (which must have at least three days in a row above 25 °C). The warmest 7-day spell on record is 4th-10th August 1975 (20.8 C); this was equalled for both 16th-22nd and 17th-23rd July 2022.
Given such high night-time temperatures, it is not surprising that the mean minimum air temperature is the highest for July since 1844. The absolute minimum of 9.0 °C is the 3rd highest for any July, exceeded only in 1983 and 1846. The mean maximum temperature is equal 5th highest on record. The mean air temperature is third equal highest on record (with 1989), exceeded only in 2013 (18.0 °C) and 2006 (18.3 °C). There was the highest mean grass minimum temperature for July since 1874.
Up until the last ten days, it had been a dry month, but the total is only a little below the 1991-2020 average, ranking 66th in a series of 173 years since 1850. Like rainfall, sunshine was close to average, not at all exceptional despite the hot weather.
Emeritus Professor Tim Burt
Department of Geography