Irish heatwave: Old Moore’s Almanac saw this coming. May: warmer than average. June: early summer, warmer than usual, with warm spells and thundery showers. July: above average temperatures, warm spells, and staycation worthy conditions right across the country. As Ireland’s most talked-about Irish heatwave in living memory grips the nation, it is looking very much like the almanac’s summer vision is already well underway.
This comes after the floods in Dublin were predicted in the 2026 edition.
Ireland’s Irish Heatwave Breaks Records Three Times in One Week
Ireland has just experienced its hottest May on record, with temperatures rewriting the history books not once, but three times in a single week. The record for the highest temperature ever recorded in May had stood since 1997, when 28.4 degrees Celsius was logged in Ardfert Liscahane, Co Kerry. That record fell on Monday 25 May, when Shannon Airport in Co Clare hit 28.6 degrees, then fell again the following day when the mercury climbed to 30.6 degrees, also at Shannon.
The record was broken yet again when Shannon Airport registered 30.5 degrees, making it the first location in Ireland to surpass 30 degrees in the month of May. For context, that is warmer than many Mediterranean destinations at the same time of year.
What Is Causing the Irish Heatwave?
Meteorologists describe a very substantial blocking event in the atmosphere, an intense area of high pressure that became stuck in place over parts of Europe and Ireland for several days, enabling heat to build progressively. Met Eireann climatologist Paul Moore noted that when very strong high pressure stacks through the atmosphere over several days, maximum temperatures can exceed those seen in similar historical situations, owing to the increased background warming caused by climate change.
In short, it is not just a fluke. Climate change is raising the baseline, and Ireland’s weather is feeling it.
Beaches, Parks and the Best Irish Heatwave Scenes
The scenes across the country were extraordinary by any Irish standard. Large crowds flocked to parks, beaches and public spaces across Dublin, where residents sought relief from conditions more commonly associated with southern Europe. Lakes, lidos and every available patch of grass became an impromptu resort, and the familiar Irish greeting of “desperate weather” was replaced, for once, with pure and uncomplicated joy.
Warnings: Thunderstorms and Health Advice
The heat did not come without caution. Met Eireann issued thunderstorm alerts for Cork, Kerry, Limerick, Waterford and Wexford, warning that scattered storms moving up from the south could be severe, bringing lightning, hail, slippy roads and impaired visibility. The thundery showers are precisely what Old Moore’s flagged for June, and their early arrival at the tail end of May suggests the forecast rhythm is already in motion.
Met Eireann also warned that temperatures above 27 degrees, combined with night-time lows staying above 15 degrees, were likely to cause heat stress and difficult sleeping conditions, while Water Safety Ireland urged caution around increased use of lakes and beaches.
Will the Heatwave Continue into Summer?
If May has delivered this, the summer ahead looks very promising indeed. Old Moore’s July forecast of staycation-worthy conditions will be music to the ears of anyone already planning a week in Kerry or Connemara. The almanac has long understood what the data is now confirming: Ireland’s seasons are shifting, and summer is arriving with a confidence it has rarely shown before. And it seems the heat will be returning! Extra hats may be on the shopping list this week.
