A status yellow low temperature and ice warning has been issued for most of the country with freezing conditions expected overnight.
The warning, which affects all of Munster and Connacht, as well as Cavan, Donegal, Monaghan, Kilkenny, Laois, Longford, Offaly, and Westmeath, will be in place from 8pm on Tuesday.
Until the warning lifts at 11am on Wednesday, Met Éireann is predicting "very cold" conditions", with minimum temperatures of -3C or lower, as well as "sharp to severe frost forming with icy stretches".
It comes as a temperature of -6C was recorded in Co Mayo on Tuesday morning amid a cold snap now set to last until at least the end of this week.
More generally, tonight will be dry and calm with a widespread sharp frost and icy stretches as well as fog in some areas. Temperatures tonight will fall back to around -3C to 0C.
Wednesday, like Tuesday, will be chilly, with overnight mist and fog stubborn to clear some areas. Temperatures tomorrow will be even colder than today with the mercury hovering between 1C to 6C. The coldest conditions are expected across the western half of the country.
Wednesday night too will be a calm, cold and frosty night with widespread fog developing. Lowest temperatures Wednesday night will range from -3C to 0C.
On Thursday, overnight frost will clear slowly, with further lingering fog likely in some areas. By early afternoon, it will be calm and rather cloudy, with some patches of light rain or drizzle at times. Thursday will be another cold day, with temperatures of 2C to 7C expected.
Thursday night will be calm but misty or foggy in places, along with frost where skies clear. There will also be some showers, according to Met Éireann. Lowest temperatures on Thursday night will range from just -1C to 3C.
At this stage, Friday looks set to be another dry day overall with some bright or sunny spells, and the possibility of lingering fog patches. There is also a chance of a few well scattered showers, mainly across southeast, west and northwest. Friday will be slightly less cold than previous days, with temperatures of 4C to 8C expected.
Friday night will be cold with clear spells and isolated showers along west and northwest coasts, with the temperatures falling back to the low single-digits in mostly light westerly breezes.
Check out the Irish Examiner's WEATHER CENTRE for regularly updated short and long range forecasts wherever you are.