January 2011

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

Mean daily maximum: 6.7
Difference from average: +0.9

Mean daily minimum: 0.3
Difference from average: +0.1

Mean air temperature: 3.5
Difference from average: +0.5

Absolute maximum: 13.6 (6th)

Absolute minimum: -6.5 (7th)

Mean grass minimum: -2.5

Absolute grass minimum: -9.9 (7th)

Number of ground frosts: 23

Number of air frosts: 15

Mean soil temperature at 30cm depth: 3.5

Mean soil temperature at 100cm depth: 5.3

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

Total for the month: 48.4
Difference from average: -10.6

Percentage of the average: 82%

Wettest day: 11.4 (6th)

Number of rain days (>0.25mm): 16

Number of wet days (=> 1mm): 12

3-month total rainfall to 31st January: 241.2
Difference from average: +62.7

6-month rainfall total to 31st January: 423.8
Difference from average: +70.1

12-month rainfall total to 31st January: 732.8
Difference from average: +83.8

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 84%

Sunshine
(all averages 1961 – 1990)

Total for the month: 69.8 hours
Difference from average: +16.0

Percentage of the average: 130%

Mean daily sunshine: 2.3 hours
Difference from average: +0.6

Sunniest day: 7.1 hours (9th)

Number of days with no recorded sunshine: 0

Wind

The mast is still broken, we hope to replace it soon.

ISSN1350-483

Comments on January 2011
Although there were some cold days, January ended up well above average temperature, mainly because of daytime temperatures being above normal. Night-time minima were only just above average. There was the highest absolute maximum since 2003. The number of ground frosts was equal to 2001 and the highest since 1998. Rainfall was a little below average but long-period totals remain well above average. It was a sunny month, well above average.

Professor Tim Burt
Department of Geography
Durham University