May 2016

NB provisional results: Some data currently lacking for 31st May, infilled from Copley.

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

Mean daily maximum: 15.1
Difference from average: +0.8

Mean daily minimum: 7.0
Difference from average: +1.4

Mean air temperature: 11.1
Difference from average: +1.2

Absolute maximum: 22.2 (8th)

Absolute minimum: 2.8 (1st)

Mean grass minimum: 5.2

Absolute grass minimum: 0.1 (1st)

Number of ground frosts: 0

Number of air frosts: 0

Mean soil temperature at 30cm depth: 12.2

Mean soil temperature at 100cm depth: 10.5

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

Total for the month: 41.7
Difference from average: -10.5

Percentage of the average: 80%

Wettest day: 11.8 (25th)

Number of rain days (>0.25mm): 9

Number of wet days (=> 1mm): 7

3-month total rainfall to 31st May: 181.0
Difference from average: 9.1

6-month rainfall total to 31st May: 449.6
Difference from average: 103.5

12-month rainfall total to 31st May: 863.2
Difference from average: 214.3

Humidity
(averages for 09:00 hours GMT)

Relative Humidity: 80%

Sunshine
(all averages 1961 – 1990)

Total for the month: 141.5 hours
Difference from average: -27.0

Percentage of the average: 84%

Mean daily sunshine: 4.6 hours
Difference from average: -0.8

Sunniest day: 11.5 hours (9th)

Number of days with no recorded sunshine: 1

Cumulative total sunshine since 1st January: 471.1 hours
Difference from average: -55.2

ISSN1350-483

Comments on May 2016
Following a disappointing April, May was a warm month, equal 29th warmest in 167 years. Minimum temperatures in particular were well above average; the mean minimum was equal 12th warmest since 1900. The best of the temperatures came early in the month with a welcome maximum of 22.2°C on 8th. Rainfall was below average, but all long-period totals remain above average, the 6-month and 12-month totals especially. Despite lower than average rainfall, hours of bright sunshine were below average too, by nearly an hour per day, reflecting the predominance of cloudy conditions with a generally easterly air flow off the North Sea.

Note that we had telephone line problems early on 1st June so some data are lacking for 31st May. Many thanks to Ken Cook for providing some provisional data from Copley. I will hope to update our data in due course.

Professor Tim Burt
Department of Geography
Durham University