A Status Yellow rain warning has been issued for counties Cork, Kerry and Waterford following a hot spell over the weekend.
The alert will be in place from 1am tomorrow until 3pm.
Met Éireann has warned of potential difficult travelling conditions, localised flooding and poor visibility.
The UK Met Office has also issued a Yellow rain warning for Antrim, Armagh, Down, Tyrone and Derry.
This notice comes into effect from midday tomorrow and is valid until 6am on Tuesday.
It forecasts that rain will be heaviest across eastern areas and will push northeast across much of Northern Ireland tomorrow, clearing Tuesday morning.
Meanwhile, a Status Yellow thunderstorm warning issued for eight counties has expired.
The warning for counties Cavan, Donegal, Monaghan, Dublin, Kildare, Louth, Meath and Wicklow came into effect at 12pm and was valid until 7.30pm.
Status Yellow rain warning issued for three counties
A Status Yellow rain warning has been issued for counties Cork, Kerry and Waterford following a hot spell over the weekend.
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