Temperatures are set to plunge by 10 degrees Celsius as June will turn chilly compared to the Mediterranean-style conditions we're enjoying at the moment.
Thursday was the hottest day of the year so far with the highest temperature of 26.8 degrees recorded at Mount Dillon, Co Roscommon.
Many parts of Leitrim basked in temperatures in the mid-20s.
However Irish Weather Online experts said that cooler air from the north will bring daytime temperatures as low as 13 degrees in the the next two weeks.
Prof Peter O'Donnell said: "The warm, dry spell is still advertised to break down mid-week, as cooler air begins to arrive from the north and northeast.
"This outcome can still be regarded as somewhat uncertain, but the trend is certainly swinging towards much cooler weather within ten days to two weeks from now, the timing is the more uncertain part than the eventual outcome, I believe.
"Temperatures could be quite a bit cooler by the middle of the second week of June than currently, and perhaps as far below seasonal averages as we are currently above them.
"That would imply mid-day temperatures in the 13-15 C range. But it will probably be a gradual change towards that outcome, taking about a week to realize."
Bank holiday weekend
In the meantime, today and the weekend will enjoy long sunny spells with highs in the mid-20s.
Saturday will be hazy and warm while Sunday, Monday and Tuesday will be hazy and warm with some showers.
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