The entire country is under a high temperature warning for the rest of the week.
Cavan, Monaghan, south Leitrim, Roscommon, Longford and Westmeath is under a status orange alert.
Temperatures exceeding 30 degrees are forecast, while it's unlikely to drop below 20 degrees at night.
The rest of country is under a yellow high temperature alert, with daytime temperatures of between 27 and 30 degrees forecast.