It was a mild, dry and sunny May for Ireland in 2025, with the average temperature among the warmest on record, and rainfall levels notably low.

That's according to the Provisional Weather Statement for May published by Met Éireann today (Wednesday, June 4).

Provisionally, the May 2025 average temperature of 12.54°C made it the sixth highest for May in 126 years of records.

In keeping with the trend of a consistent warming signal for May in Ireland, the top seven highest average May temperatures have occurred since 2008, with 2024 out in front with an average temperature of 13.08°C.

The average temperature for May 2025 was 1.85 °C above the 20th century (1901-2000) average for the month and 1.21 °C above the long-term average for the most recent climatological reference period of 1991-2020.

Blocking high pressure, positioned mostly to the north of Ireland, dominated for the first three weeks of the month with Atlantic low pressure breaking through in the final week.

The month began warm, especially in the south, before a weak cold front moved south, introducing a slightly cooler airmass.

High pressure soon re-established just to the north of the country and brought a dry and mostly sunny first week and a half, as it gradually warmed up again.  

A slack area of low pressure tried to push up from the south between Sunday, May 11 and Wednesday, May 14, introducing instability and activating some scattered showers and thunderstorms in places.

Rainfall amounts stayed low in most places. Blocking high pressure again re-established to the north between Thursday 15 and Thursday 22, bringing a lot of dry and sunny conditions, while always warmest in the midlands, south and west due to the easterly airflow.  

The abundant sunshine and slack easterly airflow intensified the marine heatwave off the south and west coasts that had been building through April.

A cold pool aloft introduced instability on Monday, May 19 and Tuesday 20, which resulted in scattered, intense thunderstorm activity. Some places saw heavy downpours while other places had little or no rain.  

Atlantic weather fronts finally broke through on Friday, May 23, introducing a slightly cooler westerly airflow.

The final week of the month saw westerly winds return with low pressure to the north steering several frontal rain bands across the country, interspersed with sunshine and showers. 

Provisional gridded rainfall data suggests May 2025 averaged around 56mm, representing 70% of the month’s long-term average from 1991-2020.

2025 ranks as the 23rd driest May in records since 1941 and the fourth consecutive year to have below the long-term average rainfall for the month.

The number of rain days ranged from eight days at a few stations to 13 days at Casement Aerodrome, Co. Dublin.

The number of wet days ranged from five at both Roches Point, Co. Cork and Johnstown Castle, Co. Wexford, to 11 at Phoenix Park, Co. Dublin.  

The number of very wet days ranged from zero at a few stations to four at Newport, Co. Mayo.  

20 weather stations across the country recorded climatological dry spells – periods of 15 or more consecutive days with less than 1mm of rainfall – from end of April into May.

Total hours of sunshine from all available locations were above the long-term average for 1991-2020, with two stations recording their highest ever monthly sunshine totals, and a couple of others their highest totals for May.