An orange weather alert remains in place for the southeast with heavy rain forecast to continue in the early part of Thursday and flooding remaining a possibility.
The alert, Met Éireann's second highest, for counties Waterford, Wexford and Wicklow has been extended until midday on Thursday.
A lesser status yellow rainfall warning is in place for Carlow, Kildare, Kilkenny and Cork.
Significant accumulations of rain water were expected overnight and today, with the Road Safety Authority (RSA) saying this could create dangers for motorists.
“Drivers need to slow down and leave a bigger space between themselves and the vehicle in front in wet weather conditions,” it said in a statement. “This is especially important on high speed roads such as dual carriageways and motorways where there is increased danger of aquaplaning.
“Flooded roads that appear shallow could be deeper than you think. They may also have trees or branches that have fallen that may not be visible. “
Road users in areas affected by heavy rain are advised to check local traffic and weather conditions before setting out on a journey.