The island of Ireland has experienced its warmest May on record, according to both the Irish meteorological service Met Éireann and the UK Met Office.

In Ireland, May 2024 was the warmest May on record with an average temperature of of 13.08°C, which is 2.53°C above the 1961-1990 long-term average (LTA) or 1.74°C above the 1991-2020 LTA for May.

According to Met Éireann, this is only the second time (in 125) that the May average temperature exceeded 13°C.

The previous warmest May was May 2008 with an average monthly temperature of 13.03°C.

May 2024: Warmest May on record. Calm, dull and thundery at times
?The Island of Ireland average May temperature was 13.08 °C, which is 2.53°C above the 1961-1990 long term average (LTA) or 1.74 °C above the 1991-2020 LTA for May
More here - https://t.co/FS5lZ5KR8h pic.twitter.com/TbQq3UNb4j

— Climate Services @ Met Éireann (@METclimate) June 5, 2024

There were no air frosts reported in Ireland for the third consecutive May. The coldest May remains May 1923 with an average temperature of 8.67°C.

Interestingly, all available monthly sunshine totals in Ireland were below their LTA for the month of May. 

Percentage of monthly sunshine values ranged from 79% (monthly sunshine total of 142.8 hours) at Shannon Airport, Co Clare to 80% (monthly sunshine total of 148.6 hours) at Casement Aerodrome, Co Dublin.

Both locations experienced their dullest May since 2014.

Monthly sunshine totals ranged from 121.8 hours (No LTA comparison*) at Gurteen, Co Tipperary to 161.1 hours (No LTA comparison*) at Valentia Observatory, Co Kerry.

The highest number of daily sunshine hours recorded for the month was 14.9 hours at Johnstown Castle, Co Wexford on May 19 and Cork Airport on May 20.

The number of dull days - days with less than 0.5 hours of sunshine - ranged from three days at both Johnstown Castle, Co Wexford, and Valentia Observatory, Co Kerry to ten days at Gurteen, Co Tipperary.

Meanwhile, Northern Ireland set a mean temperature record of 12.9°C for the month of May.

In the overall UK, May 2024’s average mean temperature of 13.1°C beat 2008’s previous record figure of 12.1°C in a series that dates back to 1884.

A spokesperson for the UK Met Office said: “While it may not have felt like it for many, with sunshine in relatively short supply, provisional figures show May was the warmest on record in our series back to 1884.

"This warmth was especially influenced by high overnight temperatures, with the average UK minimum temperature for May 1.2°C higher than the previous record.

“Rainfall was above average for the UK, while some areas in the south saw over a third more rain than average.

"In contrast, Northern Ireland and Scotland were slightly drier than average in the month.”

While it may not have felt like it for many, with sunshine in short supply, provisional figures show May and spring were the warmest on record for the UK.

Get the full details, including how warm nights influenced the figures ?

— Met Office (@metoffice) June 3, 2024

As in Ireland, sunshine amounts were below average for the UK in May. The UK saw 159.3 hours of sunshine, which was 17% fewer than average, with England, Wales, Scotland, and Northern Ireland all having below average sunshine hours.

The Met Office added that meteorological spring (March, April, and May) was the UK's warmest on record by mean temperature (a provisional figure of 9.37°C), in figures that were influenced by high overnight temperatures.