High overnight temperatures spur May to fifth warmest on record – Met Office

The UK has experienced the fifth warmest May on record, largely due to record-breaking overnight temperatures, the Met Office has said.

The warm month means that this spring overall has been the fifth warmest for the UK, in records dating back to 1884, they said.

The five warmest springs have all occurred in the last 15 years,  figures show.

For May, average temperatures for the UK were 11.8C, some 1.2C above the long-term average, but that was mostly down to the warm nights for the time of year across the UK, particularly in northern and western areas.

Average daily minimum temperatures – the lowest the mercury falls to overnight – were 7.8C in the month, some 1.5C above average, and the highest on record for May.

Average maximum temperatures for the month were 0.8C above long-term norms, with the highest individual temperature, 27.5C, recorded at Heathrow on May 17.

Despite the warm temperatures, May saw a below-average number of sunshine hours, with northern and western areas being particularly dull, the Met Office said.

Dr Mark McCarthy of the National Climate Information Centre said: “High minimum temperatures are the most notable statistic coming from May’s provisional figures, helping to bring mean temperatures for the month into the top five on record for May.

“Cloud cover has been one part of the picture for the higher-than-average minimum temperatures, with overcast skies helping to lock some heat in through the night, especially in northern and western areas.

“Warmer air from the continent has helped keep minimum temperatures up in the South and despite that lack of daytime sunshine, maximum temperatures have remained above average for most, although without any prolonged spells of very high daytime temperatures.”

Across March, April and May it was also the fifth warmest spring on record for the UK, with average temperatures for the season about 0.8C above the long-term average.

It was a relatively dry spring, with rainfall for the season down by a quarter to 76% of long-term averages across the UK and particularly low in Wales, with 58%.

Only northern areas of Scotland and some of Northern Ireland got nearer to their average rainfall totals for the time of year.

Rainfall was in short supply in March, with 58% of the average for the UK as a whole, and 68% in April.

May had near-average rain for the month across the country, although that varied between below-average levels for England and Wales, and above average for Scotland and Northern Ireland.