April 2015

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

Mean daily maximum: 13.2
Difference from average: +2.2

Mean daily minimum: 3.3
Difference from average: +0.2

Mean air temperature: 8.3
Difference from average: +1.3

Absolute maximum: 19.0 (23rd)

Absolute minimum: -1.1 (27th)

Mean grass minimum: -0.9

Absolute grass minimum: -5.6 (27th)

Number of ground frosts: 9

Number of air frosts: 2

Mean soil temperature at 30cm depth: 9.8

Mean soil temperature at 100cm depth: 8.7

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

Total for the month: 22.8
Difference from average: -24.5

Percentage of the average: 48%

Wettest day: 8.2 (12th)

Number of rain days (>0.25mm): 7

Number of wet days (=> 1mm): 5

3-month total rainfall to 30th April: 83.9
Difference from average: -88.1

6-month rainfall total to 30th April: 223.6
Difference from average: -122.6

12-month rainfall total to 30th April: 557
Difference from average: -92

Humidity
(averages for 09:00 hours GMT)

Relative Humidity: 73%

Sunshine
(all averages 1961 – 1990)

Total for the month: 188.2 hours
Difference from average: +55

Percentage of the average: 141%

Mean daily sunshine: 6.3 hours
Difference from average: +1.9

Sunniest day: 11.7 hours (22nd)

Number of days with no recorded sunshine: 1

Cumulative total sunshine since 1st January: 487.3 hours
Difference from average: +129.5

ISSN1350-483

Comments on April 2015
April was a warm month, although not exceptionally so. It was the 19th equal warmest April at Durham since 1850, but nearly a degree cooler than April 2014 (equal 7th warmest). Maximum temperatures were well above average but minima were only just above average.

April was another dry month, the 37th driest since 1850. It was the 23rd driest February to April period and all multi-month totals are now well below average. Not surprisingly, it was a sunny month, the 10th sunniest April since 1882. The total amount of sunshine this year remains well above average.

Professor Tim Burt
Department of Geography
Durham University