Met Eireann has issued a Status Yellow thunderstorm warning for Cork, Kerry and Limerick.
Forecasters say the storms are likely in some parts on Monday.
The agency warned that potential impacts include lightning damage, power outages, localised flooding and difficult travelling conditions.
The warning applies between 9am and 6pm on Monday.
Met Eireann said the weather in Munster will begin dry with sunny spells but cloudier in the southwest.
It said showers will develop later in the morning and merge into longer spells of rain for a time with some heavy falls and thunderstorms likely, especially over the south and southwest.
Highest temperatures in the region on Monday are expected to fall within 19 to 23 degrees in light to moderate easterly breezes.
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