October 2004

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

Mean daily maximum: 12.7
Difference from average: -0.5

Mean daily minimum: 6.6
Difference from average: -0.3

Mean air temperature: 9.7
Difference from average: -0.1

Absolute maximum: 16.5 (8th)

Absolute minimum: 2.5 (15th)

Mean grass minimum: 3.3

Absolute grass minimum: -1.6 (27th)

Number of ground frosts: 4

Number of air frosts: 0

Mean soil temperature at 30cm depth: 11.7

Mean soil temperature at 100cm depth: 13.2

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

Total for the month: 120.4
Difference from average: +67.9

Percentage of the average: 229%

Wettest day: 21.8 (17th)

Number of rain days (>0.25mm): 23

Number of wet days (=> 1mm): 19

3-month total rainfall to 31st October: 296.8
Difference from average: +113.1

6-month rainfall total to 31st October: 449.4
Difference from average: +118.4

12-month rainfall total to 31st October: 814.7
Difference from average: +165.7

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 84.3%

Sunshine
(all averages 1961 – 1990)

Total for the month: 70.1 hours
Difference from average: -23

Percentage of the average: 75.3%

Mean daily sunshine: 2.3 hours
Difference from average: -0.7

Sunniest day: 7.8 hours (7th)

Number of days with no recorded sunshine: 3

Cumulative total sunshine since 1st January: 1061.3 hours
Difference from average: -156.2

Wind

The mean wind speed: 11.5km/h [6.2kt]
Difference from average: -0.4km/hr

The highest gust: 88.9km/h [48kt] from 202° at 03:36 GMT on 21st

ISSN1350-483

Comments on October 2004
October was another very wet month, reversing the trend from September and sending long-term totals back well above average. It was the 18th wettest October since 1852. It was the wettest October since 2000 although the number of rain days was the same in both years.

Remarkably, for the first time this year, a monthly mean air temperature dipped below the long-term average, but only just! Sunshine reverted to the usual pattern for 2004 and fell below average yet again.

Professor Tim Burt
Department of Geography
Durham University