Cold, Wet December, Sunnier Than Average

Armagh Observatory reports that December 2014 was cold and wet, but sunnier than average.

The mean monthly temperature was 4.5 degrees Celsius (40.1 degrees Fahrenheit), approximately 0.1 degrees C cooler than the long-term (1796–2010) average December temperature at Armagh and more than 0.4 degrees C cooler than the most recent 30-year (1981–2010) December average.

The warmest day (highest maximum air temperature) was 12.4 C on the 18th, and the coolest night (lowest minimum air temperature) was –5.1 degrees C on the 29th. This was the coldest night at Armagh for 21 months, that is, since the very cold 12th March 2013, and the coldest December night for two years. There were 12 nights with air frost and 25 with ground frost.

Total precipitation amounted to 98.95 mm (nearly 3.9 inches), approximately 28 per cent more than the average December rainfall at Armagh, which is roughly 77 mm. The wettest day was the 10th, with 15.2 mm (0.6 inches), though there were two other days (23 and 16) each with around half an inch of rain, and just one day (the 2nd) with no recorded precipitation at all.

Despite the cool, wet weather, December 2014 was brighter than average with a total of approximately 53.2 hours of strong sunshine. This is some 30 per cent more than the December average at Armagh, making December 2014 the 10th sunniest December on record, shared with December 1893. The sunniest day was the 2nd, with 6.5 hours of strong sunshine.

Taking the year as a whole, 2014 can be described as wetter and warmer than average with about average sunshine, though this masks large in-year variations.

The mean annual temperature was 10.16 degrees C, nearly half a degree warmer than the most recent 30-year (1981–2010) annual average temperature at Armagh and more than one degree C warmer than the corresponding long-term (1796–2010) annual average. 2014 was the warmest year at Armagh since 2011, and the 14th warmest on record, continuing the trend of relatively warm years during the past decade or so.

Total precipitation during 2014 was 957.85mm (approximately 37.7 inches), making 2014 the wettest at Armagh for 12 years, that is since 2002, and the fifteen wettest year at Armagh since rainfall records began in 1838.

The total number of hours of strong sunshine was 1249.0. This is approximately 8 per cent less than the long-term (1881–2010) annual average but close to the most recent (1981–2010) annual average of 1247.0 hours.

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