Counties Kerry, Clare and Galway are under a status yellow rainfall warning this morning.
Met Eireann says hazardous driving conditions and localised flooding can be expected.
The warning runs until midday.
Meanwhile, due to the weather warning, prior-warning notices have been put in place at a number of Kerry beaches.
These are Ballybunnion North & South, Fenit, Ventry, Kells, White Strand, Cuas Crom, Inny Strand and Ballinskelligs.
The council says this is to advise the public of possible water quality issues, but there is no prohibition on swimming.