Monthly summary January 2009

January 2009 will be remembered as a truly winter month being the coldest January since 1997 and the 4th coldest I have recorded. The mean temperature was just 1.8°C, this being 2.2°C below the long-term average. There were 18 air frosts, which are 7 above the average and close to the record of 22 in January 1985 and also 21 in January 1987. Not only were these frosts frequent but also quite severe with a record low for January of -13.3°C during the night of the 7th. There were also some very cold days when the thermometer did not reach a positive figure, namely 6th and 9th with -1.0C° and -2.5°C respectively. The rainfall of 71.4mm was 81% of the long-term average. With a wet period from the 7th to 22nd, due to mild, moist southerly winds, resulting in the majority of the rainfall and the two wettest days on the 21st and 22nd with 14.8mm and 12.3mm respectively. There were five mornings that dawned with fog and four days with light snowfall. My analysis of the diurnal temperatures, the daily difference between the maximum and minimum, shows a gently increasing maximum, a rise of almost 2°C from the 1980’s to this century.

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