May’s weather

At the start of the month, a slackening low pressure system brought rain and showers to the south, but it was mostly dry and sunny in the north. During the first 11 days the weather was anticyclonic with mainly easterly winds, which brought plenty of warm, dry, sunny weather, especially to Northern Ireland and western Scotland, but it was cooler and cloudier in the south-east and in counties bordering the North Sea.

Around mid-may, the weather turned unsettled with bands of rain interspersed with brighter showery weather. There was a notable hot and sunny interlude for much of the UK between the 24th and 26th, with temperatures widely in the mid to high 20s celsius, followed by widespread thunderstorms on the 27th and 28th.

The provisional UK mean temperature was 12.1 °C, which is 1.7 °C above the 1981 to 2010 long-term average, making it the second warmest May in a series from 1910 (behind 2008). Mean maximum temperatures were generally about 2.5°C above normal in Scotland and Northern Ireland but nearer 1.5°C above in the south, while mean minimum temperatures were between 1 and 2°C above average in all regions.

Rainfall was above normal in Lincolnshire, East Anglia and south-eastern and central southern England but mostly below normal elsewhere, substantially so in some parts, with 83% of average overall. Sunshine was 115% of average; it was a very sunny May in Northern Ireland and western Scotland with excesses of over 50% in some places, but sunshine was close to average in East Anglia and southern England. As a whole, for the UK, it was the 10th sunniest May in a series from 1929.

The UK monthly extremes were as follows: a maximum temperature of 29.4 °C was recorded at Lossiemouth, Morayshire, on the 26th and a minimum temperature of -5.1 °C was recorded at Shap, Cumbria, on the 9th. In the 24 hours ending at 9am on the 16th, 66.0 mm of rain fell at Capel Curig, Gwynedd, and a wind gust of 54 knots (62 mph) was recorded at Culdrose, Cornwall on the 5th.