Met Eireann has issued a Status Yellow weather warning today with heavy rainfall expected.
The worst affected counties will be Carlow, Kilkenny, Laois, Wexford, Tipperary and Waterford, where between 25 and 35 millimetres of rain could fall.
Gerry Murphy, a meteorologist with Met Eireann, says there is also a risk of thundery conditions today.
He said: "Take the usual precautions in realtion to thunder, which is to not stay out in the open or under trees.
"In terms of the actual rainfall itself, people should be aware in their own local area as to the potential for spot flooding in the heavy downpours."