July 2024

SUMMARY OF THE METEOROLOGICAL READINGS AT DURHAM UNIVERSITY OBSERVATORY

July 2024

Temperatures (all temperatures in degrees Celsius; all averages 1991-2020)

Mean daily maximum: 19.6   Difference from average: -0.6

Mean daily minimum: 11.4    Difference from average: +0.1

Mean air temperature: 15.5    Difference from average: -0.3

Absolute maximum: 26.9 (19^th)

Absolute minimum: 7.2 (8^th)

Mean grass minimum: 9.8      Difference from average: +0.3

Absolute grass minimum: 4.5 (8^th)

Mean concrete minimum: 12.2

Absolute concrete minimum: 7.2 (8^th)

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: 17.1

Mean soil temperature at 1000 mm depth: 15.4

Rainfall (all totals in millimetres; all averages 1991-2020)

Total for the month: 65.6        Difference from average: +3.6

Percentage of the average: 106%

Wettest day: 15.4 (9^th)

Number of rain days (>0.1 mm): 16   Difference from average: +1

Number of wet days (=>1.0 mm): 12

3-month total rainfall to 31^st July 2024: 165.4             Difference from average: -2.3

6-month total rainfall to 31^st July 2024: 348.6             Difference from average: +43.1

12-month total rainfall to 31^st July 2024: 899.2           Difference from average: +218.2

Sunshine (all totals in hours; all averages 1991-2020)

Total for the month: 155.3                  Difference from average: -19.9

Percentage of the average:  89%

Mean daily sunshine: 5.2       Difference from average: -0.5

Sunniest day: 7.7 (4^th)

Number of days with no recorded sunshine: 3

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: 4.5

Maximum gust: 64.4 (4^th, 09:45, W)

Comments on July 2024

This was the first month with a below-average mean air temperature this year and indeed the first time a month has been below average since last July. It was the coolest first half of July (13.49 °C) at Durham since 2000 (12.96 °C). The coldest first half of July on record is 1888 (10.95 °C) with 1965 ranking next to bottom (11.67 °C). The maximum temperature only got above 20 °C for the first time on the 15^th! It is nevertheless the 65^th warmest July since 1844, demonstrating how much warming has happened in recent decades. The mean maximum ranks 82^nd highest whereas the mean minimum ranks 40^th, confirming disappointing daytime temperatures but relatively warmer nights. There were no days with a maximum above 25 °C; the July average is 2 with July 2006 having 17 days with a maximum above 25 °C.

Rainfall was very close to average whilst sunshine was below average, the 64^th dullest July on record since 1882. Altogether a disappointing month: cool, quite wet and dull.

Please note that no daily file was received from the Met Office on the 24^th. I am still awaiting an explanation and perhaps the file will arrive in due course.

Emeritus Professor Tim Burt

Department of Geography

Durham University

[email protected]