Met Eireann has issued 19 counties with a low temperature/ice warning for 15 hours.
The Status Yellow alert has been ordered by the national forecaster as temperatures are expected to drop to as low as -4 degrees on Tuesday night.
Cavan, Donegal, Monaghan, Munster, Connacht, Kilkenny, Laois, Longford, Offaly and Westmeath are all impacted by the weather warning, which comes into effect at 8pm on Tuesday evening and remains in place until 11am tomorrow morning (Wednesday December 11).
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A Met Eireann forecaster says: "Very cold tonight with minimum temperatures of -3 degrees or lower. A sharp to severe frost forming with icy stretches."
Sharing tonight's nationwide forecast, Met.ie predicts: "Dry and calm this evening and tonight with a widespread sharp frost and icy stretches; areas of fog too with some freezing fog possible. Lowest temperatures of -4 to 2 degrees."
Tomorrow will be a dry and cold day with lingering fog and mist from overnight:
"Dry with overnight mist, fog and frost stubborn to clear some areas. Sunny spells developing in parts. Cold with highest temperatures 1 to 6 degrees, coldest across the western half of the country, in a light northeast breeze.
"Another calm, cold and frosty night is expected to follow with widespread fog. Lowest temperatures of -3 to 0 degrees."
The remainder of the week looks set to be dry, frosty, icy and foggy before showers and milder weather conditions move in across the weekend.
Thursday (December 12) will be another frosty day, with some patches of light rain, and highs of 2 to 7 degrees. Friday (December 13), meanwhile, will be dry with sunny spells, with some scattered showers and temperatures ranging between 4 and 8 degrees.
