Forecaster Met Éireann says the weather is to improve this weekend.
It says temperatures will rise "considerably".
"Very warm or even hot conditions developing into next week with plenty of sunshine", it says.
Dublin got to 24°C yesterday and did not fall below 15°C overnight.
Max temps nationally today 15°C in the north to 18°C in the south. Similar tomorrow.
Temps rise considerably from this weekend.
Very warm or even hot conditions developing into next week with plenty of sunshine. pic.twitter.com/joRNjz942m— Met Éireann (@MetEireann) June 20, 2018
On Tuesday, Dublin got to 24°C, and did not fall below 15°C overnight.
Maximum temperatures nationally on Wednesday will be 15°C in the north to 18°C in the south.
There will also be similar conditions for Thursday.
Friday will also be dry with sunny spells and light northerly breezes - highest temperatures of 19°.
Saturday will see dry, calm and mostly sunny conditions with maximum temperatures of 18 to 23°.
And Sunday will be the warmer day of the two this weekend, with long spells of hazy sunshine.
Highest temperatures here will range 19 to 24°.
Into next week, the forecaster says there will be "very warm or even hot conditions" developing with sunshine.
"The warmest weather so far this year possibly on the way through this extended settled spell", it adds.