Cold, wet August, a little sunnier than average. coldest summer for 29 years

Armagh Observatory reports that August 2015 was rather cooler and wetter than average, but slightly sunnier. Taking the last three months, which together represent the meteorological summer, this was the coldest summer at Armagh for 29 years, that is, since 1986.

The average temperature during the month was nearly 14.6 degrees Celsius (58.2 degrees Fahrenheit), almost the same as the long-term (1796-2010) average August temperature at Armagh, but nearly 0.8 degrees C cooler than the most recent (1981-2010) 30-year average. There was one ground frost, on the 8th, which produced a minimum grass temperature of -0.4 C. The warmest day (highest maximum temperature) was 22.9 C, which occurred on the 18th, and the coldest day (lowest maximum temperature) was 16.4 C, on the 1st. Each of the last nine months at Armagh has been cooler than the corresponding most recent 30-year monthly average at Armagh.

The month was also rather wetter than average at Armagh, with a total recorded precipitation of 117.7 mm (4.6 inches), which is nearly 44% more than the long-term (1838-2010) average August rainfall at Armagh and 54% more than the most-recent (1981-2010) 30-year average August rainfall. The wettest day was the 23rd, with 20.2 mm (nearly 0.8 inches) of rainfall.

By contrast, despite the generally cool, showery weather, the month produced 147.2 hours of strong sunshine. This is approximately 10 per cent more than the most recent (1981-2010) 30-year average hours of strong sunshine at Armagh. The sunniest day was 12.8 hours on the 18th.

August marks the end of the meteorological summer (June, July and August). This summer was noteworthy in being much cooler than average, with a mean summer temperature at Armagh of 14.08 C, slightly cooler than the nearly equally cold summers of 2011 and 1993 (both with average summer temperatures of 14.10 C). In short, summer 2015 was the coldest summer at Armagh since 1986 (which had an average summer temperature of 13.86 C).

By contrast, summer precipitation and sunshine at Armagh were close to average. That is, there was only 15 per cent more rainfall in summer 2015 than the most recent (1981-2010) 30-year summer average at Armagh, and the number of hours of strong sunshine at Armagh was only 8 per cent more than the most recent 30-year average.

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

Last Revised: 2015 September 8th