Met Éireann has predicted temperatures as high as 30 degrees today.
A status yellow high temperature warning has been issued for eight counties.
Temperatures in Kerry, Limerick, Clare, Tipperary, Galway, Kilkenny, Laois and Offaly could exceed 27 degrees today and tomorrow.
Met Éireann is predicting highs of 30 degrees today while night-time lows aren't expected to drop below 15 degrees and also warns of possible heat stress, forest fires and uncomfortable sleeping conditions.
The alert comes into effect at midday and will remain in place until 6pm tomorrow.

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