A Status Yellow rain warning has been issued for Donegal and several other counties this evening.
It will be valid from 5pm until 6am tomorrow and also affects Cavan, Clare, Cork, Kerry, Limerick, Tipperary and Connacht.
Met Éireann is forecasting spells of rain which will be heavy and persistent at times, especially on hills and mountains with totals of between 30-60mm.
Potential impacts include localised flooding and travel disruption.
Highest temperatures today will be between 15 to 17 degrees.