Rainfall warnings are in place around the country until midday today.
It comes as a number of roads have been closed in Clifden in Co Galway after heavy rain overnight.
An orange warning has been in place for Co. Kerry since yesterday morning, with a risk of up to 70 millimetres of rain there.
A less severe warning was issued for other Atlantic coastal counties - Galway, Mayo, Clare, Cork and Limerick - with up to 50 millimetres of rain due to fall.
Gardaí in Co Galway say motorists should only travel in exceptional circumstances.
Diversions are in place in the Clifden and Cleggan areas of the county.