March 2013

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

Mean daily maximum: 5.1
Difference from average: -3.4

Mean daily minimum: -0.5
Difference from average: -2.1

Mean air temperature: 2.3
Difference from average: -2.7

Absolute maximum: 12.0 (2nd)

Absolute minimum: -3.9 (31st)

Mean grass minimum: -2.3

Absolute grass minimum: -8.1 (31st)

Number of ground frosts: 23

Number of air frosts: 19

Mean soil temperature at 30cm depth: 4.1

Mean soil temperature at 100cm depth: 5.3

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

Total for the month: 59.4
Difference from average: +8.2

Percentage of the average: 116%

Wettest day: 15.0 (18th)

Number of rain days (>0.25mm): 17

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

3-month total rainfall to 31st March: 174.6
Difference from average: +22.8

6-month rainfall total to 31st March: 482.2
Difference from average: +158.5

12-month rainfall total to 31st March: 1143.8
Difference from average: +494.8

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 78%

Sunshine
(all averages 1961 – 1990)

Total for the month: 61.7 hours
Difference from average: -43.8

Percentage of the average: 59%

Mean daily sunshine: 2.0 hours
Difference from average: -1.4

Sunniest day: 8.3 hours (2nd)

Number of days with no recorded sunshine: 7

Cumulative total sunshine since 1st January: 194.9 hours
Difference from average: -29.8

ISSN1350-483

Comments on March 2013
March 2013 came in like a lamb and went out like a lion! It started mild, with the warmest day of the month on the 2nd. It ended unseasonably cold: several days did not reach 2°C towards the end of the month and the lowest night-time temperature was on the 31st. The mean maximum was the 4th lowest since 1900, the lowest since 1969. The mean minimum was equal 10th coldest (with 1969) since 1900, the lowest since 1962. Mean air temperature was equal 8th coldest since 1850, the lowest since 1969. Looking at the 12-month running mean for mean air temperature, this now stands at 8.15°C; the last time it was this low was September 1994. The running mean was 10.16°C only a year ago.

Notwithstanding the low temperatures, rainfall was just above average, with 17 rain days recorded. Given that March 2012 was very dry, this has meant that, paradoxically, the 12-month total has risen again: the total to the end of March 2013 is once more a record for Durham, over 1100mm for the first time ever. It was also the 7th dullest March since 1882, with the lowest sunshine total for March since record-breaking 1996 (only 29.3 hours, very dull indeed).

Professor Tim Burt
Department of Geography
Durham University