Storm Frank is set to hit the country today, with fears that the resultant flooding could be even worse than that caused by pre-Christmas torrential rain.
The Atlantic storm will bring downpours, strong winds and high-risk conditions.
There is a status yellow wind warning in place for Dublin and the rest of Leinster, with gusts of up to 110kph expected this afternoon.
Meanwhile, Met Eireann announced a status orange alert for the whole west coast where winds are expected to be even stronger.
"It's a very vigorous Atlantic storm, which will bring very heavy rain and strong winds, up to storm force off the west coast," said Met Eireann forecaster Evelyn Cusack.
The public have been told to stay away from at-risk coastal areas.
Locations close to the seafront, such as piers and coastal walks, should be avoided over the next 48 hours.
Irish Coast Guard director Chris Reynolds said high waters are breaking over pier walls, and stressed that high-risk areas should be especially avoided by parents with younger children.
As conditions worsen, entire communities along the River Shannon have been told to stay indoors if possible.
An expected 100mm of rain will fall in villages and towns already devastated by Storm Desmond.
Office of Public Works official Jim Casey said water levels may exceed those experienced during that storm.
He said all low-lying areas along the Shannon catchment are at risk of potential flooding.
Flood warnings were issued again last night for large parts of counties Westmeath, Clare, Limerick. Galway, Mayo, Kerry and Cork.