A status yellow rain warning has been issued for the east coast.
It will affect Louth, Meath, Dublin, Wicklow and Wexford from 9pm on Tuesday until 2pm on Wednesday.
Met Éireann is warning of spot flooding, with rain becoming heavy and persistent.
Tuesday afternoon will see sunny spells in the north and west with just the odd shower.
Cloud thickening in the east and south, however, will bring some patchy rain to the southeast coast later.
Overnight, outbreaks of rain will spread up along Leinster and east Ulster through the night, turning heavy and persistent in parts, with spot flooding possible.
Lowest temperatures of -1 to 4 degrees, so a touch of frost couldn't be ruled out in the west and southwest.
Wednesday will be cloudy with outbreaks of rain along the eastern coasts, persistent in parts during the morning with some heavy bursts, and possible spot flooding.
It will be dry further west with occasional sunny breaks. Later in the afternoon, sunny spells will develop more widely. The highest temperatures will be from six to 13 degrees
