Galway, and four other western counties, will come under a fresh status yellow high temperature warning today.
The heat is set to intensify again today, with Galway, Cork, Kerry, Limerick, and Mayo are expected to see temperatures above 27 degrees.
The alert comes into place from 1 o'clock this afternoon until 7am on Wednesday morning, with warm, humid nights making sleeping difficult.
A nationwide heat advisory from Met Eireann remains in place until Friday, with highs approaching 30 degrees in places, and thunderstorms possible later in the week.
