October 2009

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

Mean daily maximum: 14.0
Difference from average: +0.8

Mean daily minimum: 6.9
Difference from average: +0.6

Mean air temperature: 10.5
Difference from average: +0.7

Absolute maximum: 16.4 (31st)

Absolute minimum: 0.0 (9th)

Mean grass minimum: 4.0

Absolute grass minimum: -2.8 (9th)

Number of ground frosts: 4

Number of air frosts: 0

Mean soil temperature at 30cm depth: 12.0

Mean soil temperature at 100cm depth: 13.0

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

Total for the month: 39.0
Difference from average: -13.5

Percentage of the average: 74%

Wettest day: 9.6 (6th)

Number of rain days (>0.25mm): 14

Number of wet days (=> 1mm): 10

3-month total rainfall to 31st October: 92.6
Difference from average: -82.6

6-month rainfall total to 31st October: 378.8
Difference from average: -48.5

12-month rainfall total to 31st October: 609.5
Difference from average: -39.5

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 88%

Sunshine
(all averages 1961 – 1990)

Total for the month: 75.1 hours
Difference from average: -18

Percentage of the average: 81%

Mean daily sunshine: 2.4 hours
Difference from average: -0.6

Sunniest day: 7.9 hours (3rd)

Number of days with no recorded sunshine: 3

Cumulative total sunshine since 1st January: 1239.1 hours
Difference from average: +21.6

Wind

The mean wind speed: 10.9km/h [5.9kt]
Difference from average: -1.5km/hr

The highest gust: 91.9km/h [49.6kt] from 223° at 15:18 GMT on 3rd

ISSN1350-483

Comments on October 2009
October was mild, particularly so at the end of the month with maximum temperatures above 15°C on the last four days. It was the 23rd equal warmest October in 160 years. Rainfall was again below average and the 3-month total is now well below average, although the 6-month total remains above average. Despite the mildness and below-average rainfall, it was less sunny than usual. It was a less windy month than normal, but there was a gust of 91.6 kph on the 3rd.

Professor Tim Burt
Department of Geography
Durham University