Motorists are advised to drive slowly and with extra care after heavy rain in many areas overnight.
Gardaí have warned there is a lot of surface water on the roads and there are a few reports of flooding.
The Galway to Headford road is flooded, while there is also flooding on the outskirts of Tullamore, Mullingar and on the Carlow to Athy road.
In Dublin, a 40m section of the Dodder Bank collapsed at Ringsend Bridge but there were no reports of injuries.
The bridge was reopened after safety assessment by the local council.
Today's race meeting at Leopardstown in Dublin was called off as the course is waterlogged.
The Walsh Cup final between Dublin and Kilkenny at Parnell Park in Dublin was also cancelled.
Click here for more information of cancelled sports fixtures.