August 2005

Temperatures
(all temperatures in degrees Celsius; all averages 1961 – 1990)

Mean daily maximum: 20.1
Difference from average: +1.0

Mean daily minimum: 10.8
Difference from average: +0.4

Mean air temperature: 15.3
Difference from average: +0.6

Absolute maximum: 22.1 (10th)

Absolute minimum: 7.6 (2nd)

Mean grass minimum: 11.1

Absolute grass minimum: 8.5 (2nd)

Number of ground frosts: 0

Number of air frosts: 0

Mean soil temperature at 30cm depth: 16.5

Mean soil temperature at 100cm depth: 15.5

Rainfall
(all totals in millimetres; all averages 1961 – 1990)

Total for the month: 37.1
Difference from average: -30

Percentage of the average: 55%

Wettest days: 11 (10th & 30th)

Number of rain days (>0.25mm): 8

Number of wet days (=> 1mm): 5

3-month total rainfall to 31st August: 147.9
Difference from average: -52.9

6-month rainfall total to 31st August: 279.7
Difference from average: -40.3

12-month rainfall total to 31st August: 508.9
Difference from average: -140.1

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 75.5%

Sunshine
(all averages 1961 – 1990)

Total for the month: 180 hours
Difference from average: +24.5

Percentage of the average: 116%

Mean daily sunshine: 5.8 hours
Difference from average: +0.8

Sunniest day: 6.9 hours (3rd)

Number of days with no recorded sunshine: 0

Cumulative total sunshine since 1st January: 959.3 hours
Difference from average: -41.2

Wind

The mean wind speed: 10.6km/h [5.7kt]
Difference from average: -1.1km/hr

The highest gust: 63.2km/h [34.1kt] from 243° at 14:15 GMT on 13th

ISSN1350-483

Comments on August 2005
The automatic weather station failed to operate after a power cut on 14th August. This fault was not discovered until 7th September. Mean temperatures (in italics) have been estimated using anomaly maps on the Met Office website. The first six days of the month were dry at Barker’s Haugh; the rainfall figures reported here are for the Durham Observatory therefore.

August was a little above average temperature, but not greatly so. It was a dry month, with only just over half the normal amount of rainfall. All long-period totals have fallen below average, the 12-month total significantly so. [By contrast, August 2004 was a very wet month indeed.] Sunshine was above average but the running total for the year remains well below average.

Professor Tim Burt
Department of Geography
Durham University