Met Éireann has issued a Status Yellow Weather Warning for ice tonight and tomorrow morning (January 5) as temperatures plummet nationwide.
The warning for the entire country stated that a widespread sharp frost will set in with icy stretches on many roads.
The forecaster said that temperatures as low as -3° may lead to some travel disruption.
The warning is valid until 10:00a.m on Wednesday (January 5).
Meanwhile, in Northern Ireland, the UK Met Office has issued a Yellow Warning for Ice for Antrim, Armagh, Down, Fermanagh, Tyrone and Derry.
Road users are also being warned of icy stretches which could cause travel disruption.
The warning is valid until 9:00a.m tomorrow.
Met Éireann
Met Éireann has said that conditions will be clear and very cold tonight with a sharp or severe frost setting in nationwide.
Lowest temperatures of 0 to -3° will lead to icy patches on roads and footpaths.
Tomorrow morning, the frost and ice will slowly clear to leave a cold and dry day with plenty of winter sunshine.
Temperatures tomorrow will climb to between 3° and 7°, in light westerly breezes or practically calm conditions.
On Wednesday night, southerly winds will increase in strength and rain will spread from the west to all areas.
Temperatures will fall back to between -3° and 2°, but it will become milder during the night due to the rain.
The national forecaster said that the cold conditions will continue during the week with hail, sleet and possibly snow on higher ground.
A Status Yellow Gale Warning has also been issued by Met Éireann for all Irish coastal regions for Thursday (January 6).
The forecaster said that southerly gales will develop in the early hours of Thursday morning from Mizen Head to Slyne Head to Malin Head and will extend to all coasts during the day, veering westerly.