Met Eireann have issued a freezing forecast this week with temperatures set to drop as low as -4C at times.
Snow is also on the cards in places as outbreaks of rain and sleet could turn wintry as the mercury plummets.
Thursday looks set to be the coldest night of the week but sub-zero conditions are possible as early as tonight
However by the weekend things are likely to become more settled, with daytime highs reaching double digits in places.
Here is everything you need to know:
Experts are predicting some snow could fall on Wednesday but it will be confined to higher ground in the north of the country.
However it's not all good news for those who escape the white stuff, as thunderstorms are also on the cards tomorrow.
A Met Eireann forecaster said: "Today will be largely cloudy with outbreaks of rain and drizzle, most persistent over south Connacht, Leinster and Munster. There'll be drier, clearer weather over northern parts. Highest afternoon temperatures of 10 to 12 degrees over Munster and south Leinster, with a cooler 6 to 9 degrees elsewhere in moderate to fresh southwest winds, and occasionally gusty across northern and southern coastal areas
"Outbreaks of rain will slowly clear southwards overnight with good clear spells developing. Scattered showers will affect northern and western coasts, with occasional showers penetrating further inland. Lowest temperatures overnight of 1 to 4 degrees, coldest around dawn with some localised frost and icy patches possible. While southwest winds will ease light to moderate in most areas they will increase fresh to strong and gusty along northern and western coasts later in the night.
"There'll be sunny spells tomorrow, Wednesday, with scattered showers over Connacht and Ulster, and they will become increasingly heavy as the day progresses with the chance of isolated thunderstorms and hail as well as some sleet and possibly snow on hills in Ulster. Highest temperatures of 4 to 8 degrees in moderate to fresh southwest winds, but staying strong and gusty near northern and western coast.
"Wednesday night will be cold and frosty under clear skies, it'll be mainly dry apart from scattered showers along north and west coasts, again falling as sleet and snow on hills and mountains and occasionally down to lower levels. Lowest temperatures of minus 1 to plus 3 degrees in fresh southwest winds."
And the latter half of the week will see further snow, mainly at higher ground - although there will also be plenty of dry and sunny spells in many areas.
A forecaster added: "Further scattered showers for west and north coasts on Thursday with mainly dry and sunny weather elsewhere, the showers will become more widespread through the afternoon, continuing to fall as sleet and snow over higher ground. Highest temperatures of 5 to 7 degrees and feeling even colder in mostly moderate west to northwest winds.
"Clear skies on Thursday night as showers become isolated and mostly confined to northern coasts. Lowest temperatures of minus 2 to minus 4 degrees with widespread frost and some icy patches developing in light northwesterly or variable breezes.
"A cold, bright and dry start to Friday with icy stretches on untreated surfaces. There will be good sunshine early in the day, then cloud will increase from the west during the afternoon with patchy outbreaks of rain along the west coasts by evening. Highest temperatures of 5 to 7 degrees in a freshening southerly wind.
"The rain will move eastwards over the country with strong southerly winds on Friday night, falling as sleet and snow for a time initially. Temperatures will rise with the advancing rain.
"There'll be widespread rain on Saturday with temperatures of between 9 and 11 degrees in a fresh to strong southerly wind.
"Current indications suggest the rain will clear to showers by Sunday."
