Greystones in Co. Wicklow is on flood alert after a warning was issued.
Parts of Cavan, Monaghan, Mayo, Sligo, Leitrim and Roscommon are also at risk.
It follows heavy rainfall overnight with showers expected to continue for much of today.
Between 30 to 50 millimetres of rain is forecast to fall.
Forecaster Joan Blackburn explains.
“Basically what happened was a…slow-moving system came in overnight and it’s now still sitting over Leinster, Ulster and parts of Connaught” she said.
“At the moment we’re focusing on probably the East and North, where we’re given rainfall of 20-50 millimetres during the rest of today – that’s from early this morning to the rest of today”.
“That 50 millimetres though in the mountainous areas (will be) more like 20 or 30 in low-lying land” she added.
