DULL, DAMP DECEMBER, SLIGHTLY WARMER THAN AVERAGE. 2017 SLIGHTLY DRIER AND DULLER THAN AVERAGE, BUT MUCH WARMER

Armagh Observatory, 6th January 2018: Armagh Observatory reports that December 2017 was slightly wetter and warmer than average, and with the fewest hours of strong sunshine for any December at Armagh since 2011. Taking the twelve months of 2017 together, the year as a whole was much warmer than average, slightly duller and a little drier than average, with most but not all of the dry months occurring in the first five months of the year.

Total December precipitation was 78.95 mm (3.11 inches) including 11 trace values, which is approximately 2 percent more than the average December precipitation at Armagh. The wettest day was the 13th with 19.6 mm (0.77 inches) of rainfall. Snow, snowflakes or lying snow were recorded on six days, particularly around the middle of the month..

The mean monthly temperature was approximately 5.2 degrees Celsius, nearly 0.7 C warmer than the long-term (1796-2010) December average at Armagh and 0.3 C warmer than the most recent (1981-2010) 30-year average.

The warmest day (highest maximum air temperature) was 13.9 C on the 6th, followed by 12.6 C on the 23rd. The coldest day (lowest maximum air temperature) was 2.0 C on the 9th, and the warmest night (highest minimum air temperature) was 9.8 C on the 24th. The coldest night (lowest minimum air temperature) was -4.2 C on the 11th. There were 19 ground frosts and 9 nights with air frost (minimum air temperature less than or equal to zero).

With a total of 31.8 hours of strong sunshine, December 2017 recorded less than 80 percent of the average number of strong sunshine hours for December at Armagh. The sunniest day was the 15th, with 5.4 hours of strong sunshine. This was the dullest December at Armagh for six years, that is, since December 2011.

Taking the year as a whole, 2017 was one of the warmest years on record at Armagh, with a mean annual temperature of 10.38 C. This year is now the fourth warmest calendar year at Armagh, that is, since daily temperature records began around 1795. The year was also slightly duller than average. With a total precipitation of 731.15 mm including 65 trace values, 2017 was approximately 10 percent drier than the long-term (1838-2010) annual average at Armagh, which is 812.95 mm.

The attached figures show the annually averaged temperature and the annual totals for precipitation and strong sunshine since the respective Armagh climate series began.

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

For further information please contact: Mark Bailey at the Armagh Observatory, College Hill, Armagh, BT61 9DG. Tel.: 028-3752-2928; FAX: 028-3752-7174; mebat signarm.ac.uk; URL: http://climate.arm.ac.uk

Mean Annual Temperature at Armagh (1796 to 2017)

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Annual Rainfall at Armagh (1838 to 2017)

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Annual Sunshine Hours at Armagh (1881 to 2017)

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Last Revised: 2018 January 8th