AJ (5) and Rebecca Corbett (3) from Dooradoyle enjoying the sun in the People's Park in Limerick city yesterday; left: three teenagers frolic in the sea off Blyth beach in Northumberland, in the north-east of England, as temperatures hit 22C.
Press 22; Owen humphreys/pa
At this time of the year, the temperature is often struggling to get above 12C.
But the weather yesterday was positively summery, even putting some parts of the Mediterranean in the shade, with Met Eireann recording a high of 18.6C in Co Clare
And tomorrow, the mercury is expected to reach 20C in some areas, particularly Clare and Limerick. But temperatures will fall back slightly at the weekend, when scattered showers are forecast.
"We expect Friday to hit 19C to 20C, but not everywhere," said Met Eireann's Pat Clarke.
By comparison, parts of the Med, including Malta, are expected to peak at 18C.
The average temperature here so far this month has been between 14C and 18C, four degrees higher than normal. In many parts of the country, temperatures usually struggle to get above 12C until the end of April.
But Met Eireann warned there would be some dark clouds on the horizon.
"It will be slightly cooler at the weekend with scattered showers mainly in the north and west of the country -- but I could not rule out wet weather elsewhere. It isn't going to be that settled," Mr Clarke said.
Warmest times will be around midday, for about three to four hours, with cooler evenings and mornings. Overnight temperatures will fall heading in to the weekend, but Met Eireann is not expecting it to to be cold enough to cause frost.
Meanwhile, racing fans travelling to Aintree for the British Grand National on Saturday can also expect a warm burst, with temperatures around 21C.
Britain enjoyed its warmest day of the year yesterday, with temperatures reaching 22C by early afternoon.
For holidaymakers who fled to soak up the sun abroad, however, the outlook in the eastern Med is not so good, with rain expected in Athens and Rome.