The advise comes following Met Eireann issuing a yellow alert weather warning for the county today for heavy rain.
25 to 50 millimetres of rainfall is expected, with the heaviest falls in mountainous areas.
The alert remains in place until 6am tomorrow morning.
There is surface water in many areas with reports of flooding on the N72 Mallow to Killarney road around the Ballymaquirk area and just outside of Scartaglen village there are reports of flooding there also.
Flooding is also being reported on the Tralee/Abbeydorney road near Abbeydorney village & the village itself.
There is heavy flooding at Rae cross Kilflynn on the main Tralee/Listowel Road.
There are also reports of heavy snow and sleet in many parts including Killarney, Glenflesk, and Rathmore areas.
The Road from Killarney to Molls Gap is almost impassable at the moment and motorists are asked to avoid the area.
There are also icy patches on the main Killarney/Cork Road at the county bounds.
A yellow alert is also in place in counties Limerick, Tipperary and Waterford.
A more serious orange warning applies for Cork.
Joanna Donnelly, meteorologist with Met Eireann says we’re in for a wet couple of days: