Motorists have been warned to take extra care as heavy rainfall is expected to flood roads.
Between 30mm and 50mm of rain are forecast to fall along the east and south east coast, with high tides due to add to problems.
Met Éireann said heavy rain will move across the country overnight, with intense rainfall during short periods leading to local flooding.
There will also some heavy, prolonged and local thundery showers during the day.
“Southern and eastern coastal counties will have the heaviest of the rain with accumulations of between 30mm and 50mm forecast, with values possibly higher in mountainous areas,” Met Éireann said.
“But coastal areas of the south and east have the added threat of coastal flooding due to a combination of spring tides, high seas, occasional onshore gales and low pressure values.”
Dublin City Council warned there will be three high tides during the weather alert.
Flood gates on the River Dodder have already been closed, car parks at Sandymount and Clontarf are closed overnight, and the Liffey Boardwalk defences will be closed during the morning.
Flood defences on the River Tolka are also being put in place. “There may be very localised wave overtopping in parts of Sandymount and Clontarf,” it added.
“Dublin City Council maintains a stock of sandbags at various locations for strategic purposes and will be deployed by drainage staff, if required.”
The Road Safety Authority (RSA) warned drivers to be aware of pedestrians and cyclists, keep a distance from
other cars, and to follow diversions on flooded roads.
“Sometimes roads can be closed due to their fragile state after wet weather or because they are blocked by flooding. Road users should always follow recommended routes and obey signs closing roads to traffic,” it added.
“Watch out for washed out roads, earth slides, broken water or sewer mains, loose or downed electrical wires, and fallen or falling objects.”
The Irish Coast Guard urged the public not to go out on exposed coasts, cliffs, piers, harbour walls, beaches, promenades or any other coastal areas during the inclement weather.
Huge waves can be whipped up by high seas and pose hazards to anyone close to the shoreline.
Declan Geoghegan, manager, said: “Do not attempt to cross a fast running river or flood water fords as they may be stronger and deeper than you think.
“Flooded urban areas may contain many hazards, not least of which include submerged open manholes and downed power lines.
“The combination of tides, forecast gale warnings for the next day or so, high sea conditions and swollen rivers may result in very dangerous conditions.”
PA