Some localised flooding can be expected in parts of the west over the next 48 hours.
A Status Yellow Rainfall Warning is now in place for Donegal, Galway, Leitrim, Mayo, Sligo, while a similar alert takes effect in Cork and Kerry from midday.
They're due to expire at 3am on Saturday.
Liz Walsh of Met Eireann says the worst of the rainfall will have past by late tomorrow night.
"Initially the rain is going to be heavy and persistent in western and northwestern areas, and then the rainfall warning is coming into effect for Cork and Kerry as well.
"It's valid until Saturday morning."
