There is a risk of flooding for five counties with a status yellow warning in place.
Drivers are being warned of poor visibility because of very heavy rain in the southeast.
Met Éireann said Carlow, Kilkenny, Wexford, Wicklow and Waterford will be affected until midnight tonight.
Cathal Nolan of Ireland's Weather Channel said the rain will linger later.
Mr Nolan told Newstalk: "The outlook for later today is that rain really does hang about in the southeast and indeed, in most parts of the country.
"The only area that's likely to see some drier, brighter weather, maybe a little bit of sun, is in parts of the northwest of the country. For most of us it's an overcast picture. That rain has a tendency to hang around on the east coast and into the southeast as well, so we will see outbreaks of heavy rain here for the remainder of the evening."
The poor weather conditions come after Ireland was hit by Storm Kathleen over the weekend, which left thousands of homes and businesses without power.
