Cold December

Armagh Observatory reports that December was colder, sunnier and drier than average.

The mean monthly temperature was 3.0 degrees Celsius (37.4 degrees Fahrenheit), which is about 1.7 degrees Celsius below average. The maximum air temperature was 11.5 degrees C on the 5th, whilst the lowest air temperature was -6.6 C on Christmas Day when there was snow lying. There were twenty-seven nights with grass frost and sixteen with air frost. Snow fell on seven days, 18th to 23rd, and 30th. Last month had the lowest December mean monthly temperature since 1981 (1.5 C).

The number of hours of sunshine was 53.3, that is, about 40% more than the monthly average. The total precipitation for the month was 47.6 mm (1.87 inches), that is, about 40% less than the average. The wettest day of the month was the 4th, with 15.5 mm of precipitation. Taken as a whole, the average temperature for 2009, namely 9.87 degrees Celsius, was close to the average (9.94 C) for the last twenty years. However, total precipitation for the year, namely 892.15 mm (35.12 inches) was somewhat wetter than the corresponding 20-year average, namely 818.06 mm (32.21 inches). 2009 was the second wettest year since 1981.

These data refer to observations at Armagh Observatory, which has been recording the weather at Armagh since 1795.

FOR FURTHER INFORMATION PLEASE CONTACT: John McFarland at the Armagh Observatory, College Hill, Armagh, BT61 9DG. Tel.: 028-3752-2928; FAX: 028-3752-7174; jmfat signarm.ac.uk; URL: climate.arm.ac.uk.

Last Revised: 2010 January 4th