Bright, dry November, cooler than average: Driest autumn for nine years

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The Armagh Observatory has reported that November 2016 was the driest and brightest November for three years and the coolest for six years, that is, since November 2010.

Taking the meteorological autumn months September, October and November together, autumn 2016 was slightly milder than average and the driest since the exceptionally dry autumn 2007.

Total precipitation was 41.15 mm (1.62 inches), including 7 trace values, which is approximately 55% of the average November precipitation at Armagh. This was the driest November at Armagh since 2013. The wettest day was the 8th with 18.2 mm (0.72 inches) of rainfall.

The mean temperature was approximately 5.5 degrees Celsius (42.0 degrees Fahrenheit), which is roughly 0.6 C cooler than the long-term (1796–2010) average November temperature at Armagh and nearly 1.5 C cooler than the most recent (1981–2010) 30-year average.

The warmest day (highest maximum air temperature) was 14.7 C on the 14th, and the coldest day (lowest maximum air temperature) was 2.6 C on the 24th. The warmest night (highest minimum air temperature) was 8.6 C on the 14th, and the coldest night (lowest minimum air temperature) was -2.9 C on the 20th. There were 19 ground frosts, the coldest of which (lowest minimum grass temperature) was -8.7 C, which occurred on the 24th. There were eight nighttime air frosts.

With a total of 75.5 hours of strong sunshine, November 2016 recorded nearly 18% more hours of strong sunshine than the long-term (1881–2010) average at Armagh in November, and nearly 30% more than the most recent 30-year (1981–2010) average. This was the sunniest November at Armagh for three years, that is, since 2013. The sunniest day, with 7.5 hours of strong sunshine, was the 1st, closely followed by 7.4 hours on the 5th.

Taking September, October and November together, the meteorological autumn 2016 was mild and much drier than average, and with slightly fewer hours of strong sunshine than average. With a total autumn precipitation of 144.1 mm (including 16 trace values), total rainfall was approximately 64% of the average autumn precipitation at Armagh. This was the driest autumn at Armagh for nine years, that is, since the exceptionally dry autumn 2007 (111.1 mm). The mean autumn temperature (10.32 C) was approximately 0.2 C warmer than the most recent (1981–2010) 30-year average at Armagh, and the total number of hours of strong sunshine (256.4 hours) was close to the autumn average, just 2.3% less than the most recent 30-year average at Armagh.

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