Commuters can expect heavy rain and thundery showers throughout the day, according to a Yellow Rainfall Warning issued by Met Éireann.
The meteorological service said that rainfall of between 25mm and 40mm will fall in Cork and Kerry throughout the day.
This afternoon will also see some hail and spot flooding in some parts of the country while thunderstorms are expected along the east coast.
Motorists have been warned to lower their speed throughout the country due to the wet conditions.
In Dublin a collision on the on-ramp to the M50 southbound at Ballymun is causing delays. Traffic is slow in both directions on the motorway as well as on most major roads around the city.
There is a collision causing delays in the left lane of the M11 Wexford/Dublin Road northbound at J20 Arklow North.
A local road between Bridgend and Birdstown in Donegal is closed this morning while emergency services deal with an incident.
In Cork the AA warns that the N20 Cork/Limerick Road is closed in both directions at Velvetstown, just north of Buttevant, following a crash and traffic is diverting via Doneraile.
