Return to summer scorcher in store as Met Eireann pinpoints next heat surge

Irish Daily Mirror

25-05-2025

A return of high pressure and the sunshine and warm temperatures that will come with it is on the cards for Ireland after more unsettled conditions began to dominate this weekend.
Prior to the shift in the weather, Ireland had enjoyed one of the most pleasant months of May in many a year, with a phenomenon called the 'Omega Block' leading to extended spells of dry and sunny weather nationwide.
While there's no sign of a return to that weather in the final week of the month, there are promising signs of a comeback a little bit further into June, although such signs need to be treated with the caution that accompanies any forecast beyond the short-term.
Met Éireann's extended range forecast provides one such promising sign, with the most recent forecast, published last Tuesday (May 20), suggesting that 'high pressure is expected to be the dominant factor' for the week of 9-15 June.
This will bring with it 'below average rainfall amounts and above average mean air temperatures for most of the country', a trend that is expected to be repeated in Week 4 of the forecast (16-22 June), although confidence in such a forecast so far out is said to be 'low' due to 'increasing uncertainty'.
Another promising sign of a return to more pleasant weather are the comments of Met Éireann meteorologist Paul Moore about the potential longer-term effects of the Omega Block which caused the recent fine spell.
Speaking to the Irish Mirror at the height of the glorious weather earlier this month, Moore explained that the Omega Block emerges when the North Atlantic jet stream is weak and this happens when a weather phenomenon called the Stratospheric Polar Vortex breaks down early after a cold winter.
It normally breaks down in mid-April, but this year it happened a week before St Patrick's Day.
'The influence of the breakdown of the Stratospheric Polar Vortex on the troposphere can last for two to three months,' Moore said.
He added that it causes 'high pressure [systems] to re-establish over and over again' and for this summer it means 'June, July, and August has a strong signal for higher than average temperatures for Ireland during the summer months'.
In the immediate term, there is 'huge uncertainty' around the June Bank Holiday weekend forecast, according to weather expert Alan O'Reilly of Carlow Weather, who illustrated his point with one weather model showing Ireland avoiding rain and another model showing the country practically covered in it.
Met Eireann's current forecast for next weekend is for the weather to 'continue unsettled with further rain and showers' after a week where we're set to get them every day until then.
Tuesday looks set to be the dampest day of a wet week overall, with highest temperatures stretching no higher than 17 degrees.
Check out the Met Éireann forecast for the week ahead below.
Sunday
The afternoon and evening will be blustery with a mix of sunshine and scattered showers, some of which will be heavy. Noticeably cooler and fresher day than of late with highest temperatures of 11 to 16 degrees, coolest in the northwest, in fresh to strong and gusty westerly winds, strongest along the west coast.
Clear spells for much of the night with scattered showers continuing, especially in the west, while it'll become drier in the east. Later in the night, cloud will build from the west. Lowest temperatures of 6 to 10 degrees with winds decreasing mostly moderate and backing southwesterly, still fresh at times in western coastal parts.
Monday
Cloud will continue to build from the west tomorrow morning with outbreaks of rain extending eastwards. The rain will turn heavier for a time later in the afternoon and into the evening before clearing into the Irish Sea with sunny spells and well scattered showers following. Highest temperatures of 11 to 16 degrees, mildest in the south, in moderate to fresh and gusty southwest winds, veering westerly later and increasing strong for a time in western and southwestern coastal parts.
Clear spells at first with well scattered showers on Monday night, mainly over the northern half of the country. The showers will ease as cloud builds, with rain following into the southwest by morning. Lowest temperatures of 6 to 10 degrees in moderate westerly winds, fresh near Atlantic coasts.
A wet day with spells of rain tracking eastwards through the day. Some sunny spells will develop later in the day as the rain begins to clear to showers. Highest temperatures of 14 to 17 degrees generally, a little cooler in Ulster. Light southerly or variable winds will become southwesterly and increasing moderate to fresh and gusty.
A mix of cloud and clear spells with showers or longer spells of rain. Mild and humid with temperatures not falling below 8 to 12 degrees in moderate westerly winds.
Wednesday
Sunny spells and showers in the morning before turning mostly cloudy with outbreaks of rain pushing in from the west. Highest temperatures of 14 to 17 degrees generally in moderate westerly winds.
Thursday
Sunny spells and well scattered showers in the morning before cloud and outbreaks of rain push in from the southwest. Highest temperatures again of 14 to 17 degrees generally in light to moderate westerly winds.
Further outlook
Current indications suggest that Friday and the weekend will continue unsettled with further spells of rain and showers.