December 2011
This month was in direct contrast to the extremely cold December of last year. The mean temperature was 5.6C which is 1.3C above the long-term average and the warmest since 2006. With the wind predominantly from a westerly direction we had no severe weather and only five air frosts, the most severe being only -3.5C in the early hours of the 10th. The westerlies brought many damp and wet days making it the first month since August with above average rainfall. The wettest day was the 12th with 18.8mm and the total rainfall was 89.5mm, just slightly above the long-term average of 88.4mm. There were three days with snow showers that did not last very long on the ground although the morning of the 17th brought treacherous conditions on paths and roads as a rain shower in the early morning turned into sheet ice as it came into contact with the frozen ground.
2011
The average rainfall in December broke the driest 12-month spell of rainfall since July 1997 but did not alter the fact that 2011 was the driest year since 1996 and the second driest I have recorded.
The total of only 39 air frosts (=<-0.1C) was the second lowest daily count since my records began in 1984 and only two more than the previous record of 37 noted in 2002. Another record for air frosts was set with the latest date for the first air frost of the autumn, which occurred on 23rd November. Previously the years 2004 and 2005 had the latest date for the first autumnal air frost on 13th November.
It was the second warmest year since 2006 (10.8C) with a mean of 10.7C, which is only fractionally lower. The third warmest year was 2002 with a mean of 10.6C.
The solar energy recorded in 2011 was 5% less than in 2011, the first year that I have been able to keep such records. November produced much less energy than last year whereas December gave an increase of 35%.
