March 2021

Temperatures (all temperatures in degrees Celsius; all averages 1991-2020)

Mean daily maximum: 11.0 Difference from average: +1.1

Mean daily minimum: 3.9 Difference from average: +1.4

Mean air temperature: 7.5 Difference from average: +1.3

Absolute maximum: 20.8 (31^st)

Absolute minimum: -1.4 (1^st)

Mean grass minimum: 2.1

Absolute grass minimum: -4.4 (7^th)

Mean concrete minimum: 2.9

Absolute concrete minimum: -2.7 (7^th)

Number of ground frosts: 6

Number of air frosts: 4

Mean soil temperature at 300 mm depth: 10.4

Mean soil temperature at 1000 mm depth: 8.0

Rainfall (all totals in millimetres; all averages 1981-2010)

Total for the month: 24.0 Difference from average: -17.3

Percentage of the average: 58 %

Wettest day: 7.6 (10^th)

Number of rain days (>0.1 mm): 15

Number of wet days (=>1.0 mm): 7

3-month total rainfall to 31^st March 2021: 241.0 Difference from average: +69.0

6-month total rainfall to 31^st March 20201: 477.6 Difference from average: +131.4

12-month total rainfall to 31^st March 2021: 805.4 Difference from average: 156.4

Sunshine (all totals in hours; all averages 1981-2010)

Total for the month^*: 112.8 Difference from average: -7.7

Percentage of the average: 94%

Mean daily sunshine: 3.6 Difference from average: -0.3

Sunniest day: 9.3 (30^th)

Number of days with no recorded sunshine: 1

Cumulative sunshine since 1^st January: 252 Difference from average: -14

^*Note that the monthly sunshine total is now calculated from the UKMO E&NE regional total. Daily sunshine totals quoted here and in the data summary are uncorrected.

Wind (kph; all data from the West Building roof, Lower Mountjoy campus)

Average wind speed: 7.5

Maximum gust: 74.0 (28^th, 0930, W)

Comments on March 2021

Two very warm days at the end of the month (30^th: 17.1 ˚C; 31^st: 20.8 ˚C) helped raise the mean air temperature to 7.5 ˚C, the 9^th equal warmest March at Durham since 1850. The maximum on the 31^st is the 7^th highest March maximum on record. Durham’s warmest ever March day was 28^th March 2012: 21.8 ˚C. The number of air frosts was relatively low (4); only 13 Marches have had a lower total since 1900. There was the second equal lowest total of ground frosts (6, with 1938), beaten only in 1960 (3).

It was a dry month, with only just over half the average amount; the wettest day received only 7.6 mm. This was the 43^rd driest March at Durham since 1850. Despite the low rainfall total, the number of rain days was exactly average. Given the relatively high number of rain days, sunshine was just below average, reflecting often cloudy conditions.

Emeritus Professor Tim Burt

Department of Geography

Durham University