Heavy rain overnight has left many areas of the country under heavy floods today.
The River Blackwater in Co Cork burst its banks, some homes and businesses in Mallow have been flooded and a flood alert has been issued for Fermoy.
Motorists were warned of difficult conditions in other areas, particularly in the south and east.
Flooding and surface water left many roads impassable this morning, according to AA Roadwatch. Roads are closed in counties Carlow, Cork, Kilkenny, Offaly, Waterford and Tipperary.
Aidan Weir, a senior engineer with Cork County Council, said: "There's very little can be done once the Blackwater floods.
"We have been working through the night. We've been warning the residents in these areas and providing sandbags to them as required," he said.
"But once it comes to a certain level there is very little that can done to alleviate the situation in those locations."
Mr Weir urged affected residents and businesses in the Spa, Park Road and Bridge Street areas of Mallow to turn power off and move valuables upstairs.
Although the rains cleared from the rest of the country - with floods reported in Wicklow, Carlow, Kilkenny, Offaly Dublin, Waterford and Tipperary - the south remained on high alert.
Staff of Wicklow County Council were out early to clear flooding in many areas, according to senior executive officer with the roads department Frank O'Toole.
He said that although there was "nothing major" in terms of flooding, there was flooding on the Mill Road in Greystones, from the Beehive into Wicklow town, on the N81 at Crosschapel, adjacent to Baltinglass and in Avoca.
He added all areas that had suffered flooding had been more or less cleared by 10am or 11am.
A mudslide resulted in the closure of the N11 at Kilpedder earlier today. The road has now reopened. There was also flooding reported in Greystones, Kilcoole and other areas of Co Wicklow.
Senior engineer Liam Fitzgerald of Carlow County Council said there had been flooding in a number of places, including a couple of feet of water on the R705, the Bagenalstown to Borris road.
Mr Fitzgerald said council staff had been out since 2am in a bid to anticipate where some of the flooding would arise, and clearing away flood water.
Met Éireann said the rain will continue in many areas today, but brighter weather will spread to all areas from the west during the day. A few scattered showers may follow later in the day.
Met Éireann meteorologist Joan Blackburn said the bulk of the country-wide heavy rain that caused the floods has now cleared.
Additional reporting: PA