Met Éireann has warned of heavy rain and localised flooding across the western half of the country on Thursday and Friday.
The forecaster said a "band of rain was approaching from the Atlantic" that would lead to persistent and heavy rain in places.
It said this could cause river flooding and localised surface flooding.
A weather advisory has been issued for Clare, Cork, Kerry, Limerick, Donegal, Connacht.
Met Éireann said the advisory would be updated tomorrow and further warnings could be issued.
The current advisory is valid from today until 6am Saturday.