As temperatures are forecast to reach 27 degrees on Wednesday, Met Éireann has issued a status yellow weather warning for thunderstorms in counties Clare, Kerry and Limerick.
The warning covers localised flooding, lightning and difficult travelling conditions and is valid from 3pm to 9pm.
The national forecaster said Wednesday would generally be warm and humid with good sunny spells. However, showers are expected to move in from the southwest through the afternoon and evening, and some of these could be heavy with a chance of thunder and lightning.
Highest temperatures will range between 21 and 27 degrees with light to moderate southerly winds.
RM Block
Temperatures are not expected to fall below 14 degrees overnight. Thursday should be cloudy at first but with long spells of sunshine breaking through in the afternoon and evening as showers ease. Highest temperatures will reach 21 to 25 degrees in light to moderate southwest breezes.
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Friday will see further sunny spells with light showers easing through the day to leave longer periods of sunshine later on.
Highest temperatures are expected to be in the range of 21 to 25 degrees with light easterly or variable breezes.
The outlook for the weekend is for continued warm and dry conditions with temperatures generally in the low to mid-20s, and with light easterly breezes.