"Persistent" rain will lash the west of Ireland today before moving across the country.
While it'll remain dry in the east until evening time, it'll be a washout in the west.
And Met Eireann have warned that it will be "colder than normal" in the coming days with further heavy rain and a risk of sleet expected on Friday.
The national forecaster revealed we'll see a cold Friday night with a slight to sharp ground frost.
Meanwhile, this morning will be cloudy with a little hazy sunshine in the east with highs of 11C or 12C.
Tomorrow will be bright and dry in many areas with a slight frost in the north in the morning.
A forecaster said: "A cool day with varying cloud and sunny spells. Well scattered showers also - some heavy in the west.
"Moderate southwest winds veering west and increasing fresh and gusty in the north. Highest temperatures of 9C to 12C."
Looking ahead to the bank holiday weekend, a forecaster revealed rainfall will be above the norm in the south and east and temperatures will fall.
They said: "Rain will quickly spread northeast to all areas during the morning with fresh south or southeast winds.
"The rain will be heavy and continuous across the south and east especially and may give localized flooding, and may turn to sleet over north midlands areas and on high ground.
"The rain will clear southeast followed by a cold Friday night with slight to sharp ground frost."
And Saturday will be cold and bright day with good sunny spells. Most areas will be dry but scattered rain or hail showers will affect the north and northwest. Moderate northwest winds and temperatures will only reach highs of 8C.
