Drivers are being warned of poor visibility because of very heavy rain in the South East.
There's a risk of flooding and difficult travelling conditions, with a yellow warning for rain in place.
Met Eireann says Waterford, Carlow, Kilkenny, Wexford, Wicklow, are affected until midnight tonight.
Overall, Monday will be a predominantly wet day with rain expected in most areas through the morning but the northwest of the country should escape the worst of the rainfall.
"Rain will extend to most areas during Monday morning but parts of the very far northwest of the country may hold dry," a Met Eireann spokesperson said.
"The rain will persist for much of the day and will be heaviest in the southeast with the likelihood of localised flooding. Winds will be light and variable at first but will become north to northwesterly and increase moderate to fresh, but winds will be strong along south and southwest coasts. Cooler than the weekend, with afternoon temperatures of only 5 to 10 degrees."
Of Monday night, Met Eireann said: "The rain will slowly clear from the east and will be followed by clear spells and scattered showers. Lowest temperatures of 3 to 6 degrees with a moderate northwesterly wind."
For the latest Waterford News and Sport, tune into WLR News on the hour and download the WLR App for news on demand.
