November 2010

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

Mean daily maximum: 7.6
Difference from average: -1.1

Mean daily minimum: 1.8
Difference from average: -1.0

Mean air temperature: 4.7
Difference from average: -1.0

Absolute maximum: 16.1 (4th)

Absolute minimum: -8.7 (28th)

Mean grass minimum: 2.9

Absolute grass minimum: -4.6 (10th)

Number of ground frosts: 18

Number of air frosts: 11

Mean soil temperature at 30cm depth: 7.8

Mean soil temperature at 100cm depth: 10.0

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

Total for the month: 135.6
Difference from average: +73.6

Percentage of the average: 219%

Wettest day: 22.8 (22nd)

Number of rain days (>0.25mm):

Number of wet days (=> 1mm):

3-month total rainfall to 30th November: 273.4
Difference from average: +103.3

6-month rainfall total to 30th November: 456.2
Difference from average: +115.7

12-month rainfall total to 30th November: 770.6
Difference from average: +121.6

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity:

Sunshine
(all averages 1961 – 1990)

Total for the month: 76.3 hours
Difference from average: -10.2

Percentage of the average: 115%

Mean daily sunshine: 2.5 hours
Difference from average: +0.3

Sunniest day: 6.7 hours (12th)

Number of days with no recorded sunshine: 2

Cumulative total sunshine since 1st January: 1172.1 hours
Difference from average: -111.5

ISSN1350-483

Comments on November 2010
For the second month in a row and the sixth month this year, mean air temperature fell below average. It was the coldest November in Durham since 1993. The mean maximum was the coldest since 1996 and the mean minimum the lowest since 1998. The absolute maximum of 16.1°C on the 4th was the highest for November since 1996 and the 4th highest since 1962 (when my records begin); on the other hand, the absolute minimum of -8.7°C on the 28th was the lowest since 1962. The maximum on the 27th was only 0.2°C. The 12-month running mean is now at its lowest since January 1997. There were 18 ground frosts recorded (equal with 1996 and 1998 and the highest since 1985) but because of snow, recorded grass minima at the end of the month are probably higher than they would have been for bare ground.

Total precipitation was 135.6mm, a lower total than November 2009, but much of it fell as snow this year. This was the 7th wettest November since 1850 at Durham. The wettest days came as rain at the start of the month: the 2nd (22.1mm) with the 4th (19mm) not far behind. Not surprisingly, all three measures of long-term rainfall are now well above average. Despite all the rain and snow, hours of bright sunshine were just above average.

Professor Tim Burt
Department of Geography
Durham University