A status yellow rainfall warning has been issued by Met Eireann for several counties across the country.
Wicklow, Donegal, Galway, Mayo, Cork and Kerry will all be affected.
Due to the heavy rain that was promised today, accumulations of over 30mm are likely on higher ground.
The rainfall warning is in place until midnight tonight.
Early tonight, Met Eireann has forecast that rain will clear eastwards and moderate southwesterly winds will fall light with some mist or fog patches forming.
Lowest temperatures will fall to around 2 to 4 degrees.
However, rain is forecast to linger along the southeast and south coasts and return by morning with lowest temperatures there staying around 4 to 6 degrees.
Further heavy rain is promised on Saturday, with the rain spreading northwards in the morning and continuing through the afternoon and evening.
Meanwhile, temperatures in the afternoon will range between 8 or 9 degrees and winds light and variable in direction.
On Sunday, many places will be dry early in the morning but Met Eireann has promised further outbreaks of rain during the afternoon and evening while temperatures remain largely unchanged.
Next week will start off with a bright day on Monday with good sunshine, however heavy showers are forecast to develop countrywide in the afternoon.
Current indications suggest that Tuesday will be the driest day of next week with sunny spells and just a few showers.