May 2005

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

Mean daily maximum: 14.9
Difference from average: +0.6

Mean daily minimum: 6.2
Difference from average: +0.7

Mean air temperature: 10.6
Difference from average: +0.6

Absolute maximum: 19.4 (3rd)

Absolute minimum: -0.8 (11th)

Mean grass minimum: 4.9

Absolute grass minimum: -1.7 (11th)

Number of ground frosts: 1

Number of air frosts: 1

Mean soil temperature at 30cm depth: 12.3

Mean soil temperature at 100cm depth: 11.0

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

Total for the month: 19.8
Difference from average: -32

Percentage of the average: 38%

Wettest day: 7.0 (4th)

Number of rain days (>0.25mm): 12

Number of wet days (=> 1mm): 8

3-month total rainfall to 31st May: 131.8
Difference from average: -19.4

6-month rainfall total to 31st May: 206.6
Difference from average: -102.5

12-month rainfall total to 31st May: 650.6
Difference from average: +1.6

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 69%

Sunshine
(all averages 1961 – 1990)

Total for the month: 164.6 hours
Difference from average: -3.9

Percentage of the average: 97%

Mean daily sunshine: 5.3 hours
Difference from average: -0.1

Sunniest day: 11.9 hours (12th)

Number of days with no recorded sunshine: 0

Cumulative total sunshine since 1st January: 491.1 hours
Difference from average: -35.2

Wind

The mean wind speed: 14.1km/h [7.6kt]
Difference from average: +1.7km/hr

The highest gust: 87km/h [47kt] from 194° at 14:17 GMT on 28th

ISSN1350-483

Comments on May 2005
Although above average temperature, May was nevertheless somewhat disappointing, and the coolest May since 1997. That the warmest day was on the 3rd and the sunniest day was on the 12th suggests that the expected heat and sun towards the end of the month did not materialise. It was, however, a dry month: exactly the same total as a year ago but both Mays only the driest since 2001. There was a notable gust on the afternoon of Saturday 28th of 87km/h.

Professor Tim Burt
Department of Geography
Durham University