January 2015

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

Mean daily maximum: 7.1
Difference from average: +1.3

Mean daily minimum: 1.4
Difference from average: +1.2

Mean air temperature: 4.3
Difference from average: +1.3

Absolute maximum: 13.3 (1st)

Absolute minimum: -3.2 (30th)

Mean grass minimum: -0.6

Absolute grass minimum: -6.9 (30th)

Number of ground frosts: 19

Number of air frosts: 13

Mean soil temperature at 30cm depth: 4.7

Mean soil temperature at 100cm depth: 6.9

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

Total for the month: 46.6
Difference from average: -12.8

Percentage of the average: 79%

Wettest day: 9.0 (31st)

Number of rain days (>0.25mm): 14

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

3-month total rainfall to 31st January: 137.6
Difference from average: -34.4

6-month rainfall total to 31st January: 273.6
Difference from average: -72.6

12-month rainfall total to 31st January: 588.4
Difference from average: -60.6

Humidity
(averages for 09:00 hours GMT)

Relative Humidity: 79%

Sunshine
(all averages 1961 – 1990)

Total for the month: 97.1 hours
Difference from average: +43.3

Percentage of the average: 180%

Mean daily sunshine: 3.1 hours
Difference from average: +1.4

Sunniest day: 7.2 hours (30th)

Number of days with no recorded sunshine: 1

Note that no observations were available for 18th January

ISSN1350-483

Comments on January 2015
Although January felt wintry, especially at the end of the month, it was in fact well above average temperature, helped by some very mild days in the first half of the month. It was cooler than last January but still equal 37th warmest in 167 years. With a maximum of 13.3°C, it must have been one of the warmest New Year’s Days ever. It was a dry month with a maximum daily total of only 9mm. Most significantly, this was the sunniest January at Durham since records began in 1882, beating the previous record holder 2007 by 3 hours. Interestingly, five of the sunniest Januaries at Durham have been this century.

Professor Tim Burt
Department of Geography
Durham University