A yellow weather warning has been issued for the entire country for high temperatures on Tuesday.
Met Éireann says temperatures will reach over 27 degrees in many areas.
The warning is in place from 10.00am until 8.00pm.
In its outlook, the forecaster says Tuesday will see another warm and humid night with showers continuing in northern and western areas - but not as intense.
It will be mainly dry elsewhere, with lowest temperatures of just 13 to 16 degrees.
While Wednesday will be warm and humid in the east and rather cloudy, but mostly dry, with just the odd shower.
Brighter and fresher conditions in the west will extend to all areas by the afternoon.
Wednesday will see highs of 17 to 21 degrees, warmest in the far south.
Thursday will see some scattered showers in the afternoon, but still highs of 20 degrees - and Friday brings a band of rain followed by scattered showers crossing the country eastwards.
And the weekend is forecast to be changeable with a lot of dry weather, but rain or showers affecting western coastal counties and parts of the north.
Meteorologist Joanna Donnelly told Newstalk Lunchtime today and tomorrow are the best forecast.