Monthly summary July 2011

July 2011 was the coldest since 1993. Both the mean maximum and mean minimum were 1.2°C below the long-term average. The warmest day was the 4th with a maximum of 24.7°C but this is only 3°C above the mean for the month. There were several cool nights with the lowest dropping to just 3.9°C in the early hours of the 14th. The rainfall totalled 49.5mm, which is 83% of the long-term average. Interestingly the number of wet days, defined as a daily total equal or greater than 1mm, has risen since the 1980’s from an average of 8 per month to 10. The maximum daily total was 14.5mm on the 16th.

Monthly summary July 2010

July gave us another month with weather more fitting the season. The mean temperature was 1.1°C above the long-term average and was the fifth hottest July I have recorded. The hottest day was on the 9th when the thermometer peaked at 29.0°C. The total rainfall of 33.5mm was only 55% of the long-term average making it the driest July since 1999. The number of completely dry days (15) belies the fact that on several days there were light showers which did not produce any large quantity of precipitation, the wettest day on the 15th totalled just 7.6mm.

The last four months have all been drier than normal making this period the fourth driest on record with just 55% of the long-term average. The driest year was in 1995 with 108.7mm compared with the wettest in 2007 of 409.7mm. With only 128.1mm this year it is 105mm below the long-term average.