A warning for high temperatures in Leinster and Munster comes into effect from tomorrow.
Met Eireann is forecasting highs of 27 to 29 degrees on Thursday to Saturday.
It's warning it could be uncomfortably warm at night, as temperatures won't drop below 15 degrees in the coming days.
Meteorologist, Joanna Donnelly, says the alert was issued as we aren't acclimatised to such warm conditions overnight.
"We issued these warnings as the overnight temperatures aren't going to fall below 15 degrees.
"It's 15 degrees on the minimum temperature and 27 degrees on the high temperature, so from Thursday we're going to see the temperatures going over that 27 degree mark, and not falling below 15 degrees in the overnight temperatures."
