COOL AUGUST, WITH RAINFALL AND SUNSHINE CLOSE TO AVERAGE. WETTEST SUMMER AT ARMAGH FOR FIVE YEARS

Armagh Observatory, 2nd September 2017: Armagh Observatory reports that August 2017 at Armagh was slightly cooler than average with near-average rainfall and sunshine. The meteorological summer (June, July and August) was mild, but duller and wetter than average.

Total precipitation was 77.95 mm (approximately 3.1 inches) including 5 trace values, that is, 77.70 mm if trace values are ignored. This is 95% of the long-term (1838-2010) average August rainfall at Armagh and just 2% more than the most recent (1981-2010) 30-year August average. Among several days with heavy, thundery showers, the wettest day was the 22nd, recording 22.5 mm (approximately 0.9 inches) of rainfall. That day was unusual also in the report of a fox seen crossing the Human Orrery.

August 2017 recorded a total of 130.5 hours of strong sunshine, which is approximately 91% of the long-term (1881-2010) average number of hours of strong August sunshine at Armagh, and just 2% less than the most recent (1981-2010) 30-year August average. The sunniest day was the 9th, with 11.5 hours of strong sunshine.

The mean temperature was 15.1 degrees Celsius (59.2 F), approximately 0.5 C warmer than the long-term (1796-2010) average August temperature at Armagh and 0.3 C cooler than the most recent (1981-2010) 30-year August average.

The warmest day (highest maximum air temperature) was 22.3 C, which occurred on the 11th. The coolest day (lowest maximum air temperature) was 15.9 C on the 29th, and the coolest night (lowest minimum air temperature) was 5.7 C on the 13th. The warmest night (highest minimum air temperature) was 15.7 C on the 22nd. There was one ground frost, on the 13th, which produced a lowest minimum grass temperature of -1.1 C.

The meteorological summer, that is, the months June, July and August, was mild, dull and wet. The average summer temperature at Armagh was approximately 0.2 C warmer than the most recent (1981-2010) 30-year summer average at Armagh. However, the number of hours of strong sunshine was nearly 8% fewer than the corresponding most recent 30-year summer average, and the total rainfall was nearly 21% greater than the corresponding most recent 30-year summer average. Following a very dry autumn, winter and spring, this was the wettest summer at Armagh for five years, that is, since summer 2012.

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: 2017 September 5th