Extreme weather events to become 'new normal', Met Éireann warns

Big waves smashed against the rocks in Rosscarbery, Cork, during Storm Babet in October 2024. Picture: Andy Gibson

Extreme weather events are going to become more normal in Ireland, Met Éireann has warned.

In its round up of weather during 2024, it has also warned that Ireland is getting warmer, wetter, and more prone to storm surges and coastal flooding.

Compound events — involving multiple climate impact drivers occurring at the same time — are on the rise, the national meteorological service warned.

Seven of the top 10 warmest years in Ireland have occurred since 2005, with 2024 the fourth warmest year on record.

Sea surface temperatures (SST) across the North Atlantic have continued at, or near, record-high levels and this is contributing to higher than average mean temperatures and increased moisture content in the atmosphere over Ireland.

Although 2024 was drier overall than average, Met Éireann said there were many instances of heavy or intense rainfall which led to flooding. The latest Irish climate change projections indicate further warming in the future.

“This temperature change means the likelihood of extreme weather events occurring has increased,” the forecaster said.

“Irish rainfall patterns are expected to change, with an increase in both dry periods and heavy rainfall events. Global sea levels continue to rise.

 Parts of West Cork are again experiencing heavy falls of snow. There was blizzard conditions on the N71 at Barnageeha between Bantry and Ballydehob on Monday. Picture: Andy Gibson.

“As a result, storm surge and coastal flooding risk around Irish coasts is expected to increase along with ‘compound events’ involving a combination of heavy rainfall and high tides.

“It is currently unclear how the frequency and intensity of storms impacting Ireland will change with climate change.

“There is high confidence, however, that maximum rainfall rates associated with these storms will increase with warming.”

Annual air temperature

Climatologist Paul Moore added: “2024 was Ireland’s fourth warmest year on record, even though it may not have always felt that way, especially during the cooler than average summer months.

“It was often cloudy during 2024 and this, along with continued high sea surface temperatures across the North Atlantic, led to higher night-time temperatures being more influential — which drove the overall average temperatures up."

The average annual air temperature for Ireland in 2024 was 10.72 °C, which was 1.17°C above the 1961-1990 long-term average or 0.55°C above the most recent 1991-2020 long-term average. It was 0.49 °C cooler than 2023, which was the warmest year on record.

The five warmest years on record are 2023, 2022, 2007, 2024 and 1945. Seven of the top 10 warmest years have occurred since 2005.

May was the warmest May on record, and October was not only mild everywhere but also dryer than average for most — apart from the Southwest. December was the eighth month in 2024 with drier than average conditions.