June 2007

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

Mean daily maximum: 17.5
Difference from average: 0.0

Mean daily minimum: 9.9
Difference from average: +1.3

Mean air temperature: 13.7
Difference from average: +0.7

Absolute maximum: 23.7 (11th)

Absolute minimum: 5.6 (1st)

Mean grass minimum: 8.6

Absolute grass minimum: 1.3 (30th)

Number of ground frosts: 0

Number of air frosts: 0

Mean soil temperature at 30cm depth: 15.8

Mean soil temperature at 100cm depth: 14.3

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

Total for the month: 111.8
Difference from average: +60

Percentage of the average: 216%

Wettest day: 19 (15th)

Number of rain days (>0.25mm): 18

Number of wet days (=> 1mm): 14

3-month total rainfall to 30th June: 171.6
Difference from average: +20.5

6-month rainfall total to 30th June: 312.4
Difference from average: +9.6

12-month rainfall total to 30th June: 651.4
Difference from average: +2.4

Humidity
(Averages for 09:00 hours GMT)

Relative Humidity: 84%

Sunshine
(all averages 1961 – 1990)

Total for the month: 101.5 hours
Difference from average: -62.2

Percentage of the average: 62%

Mean daily sunshine: 3.3 hours
Difference from average: -2.2

Sunniest day: 10 hours (1st)

Number of days with no recorded sunshine: 7

Cumulative total sunshine since 1st January: 712 hours
Difference from average: +21.9

Wind

The mean wind speed: 8.0km/h [4.3kt]
Difference from average: -3.6km/hr

The highest gust: 50km/h [27kt] from 284° at 14:12 GMT on 6th

ISSN1350-483

Comments on June 2007
While May was disappointing, June felt dismal. Nevertheless, daytime maximum temperatures were exactly average for the time of year, while night-time minima were a little above average. June was overall just a little above average temperature therefore, the 15th month above average in a row. The absolute maximum was lowest for June since 2002, but the absolute minimum was one of the higher on record, 4th equal highest since 1962.

June was a very wet month, but not like many places nationally, the wettest on record. It was marginally wetter than 2003 and thus the wettest since 1997 (190.1mm), which is only exceeded by 1980 (191.4mm). Overall, this was “only” the 7th wettest June at Durham since 1852. It had only the largest number of rain days in June since 2000. Not surprisingly, all long-term totals returned to just above average.

June was a gloomy month, the worst June for sunshine since 1987 (the record holder with only 89.4 hours of bright sunshine), and overall the 4th lowest total on record since 1882. There were 7 days with no sunshine at all, a total not experienced in June since 1997. It was less sunny than May, which was itself less sunny than April. I thought this ‘reverse’ sequence must be unique, but in fact it has now happened 7 times in the April-June period since 1882, most recently in 2002 (The others are 1902,1912, 1954, 1984, 1990).

Finally, it was rather less windy than normal with the lowest mean wind speed since 1999.

Professor Tim Burt
Department of Geography
Durham University