Temperatures are expected to drop to -2 degrees in the first half of this week, with Met Éireann forecasting widespread frost and icy patches throughout the country.
The national forecaster said there were would be scattered showers over the north and west of the country on Monday night, with some isolated showers extending inland. These showers may become wintry over higher ground, it said.
Lows of -2 to 2 degrees with a widespread frost, and some icy patches are predicted, with the weather becoming less cold by morning.
Tuesday is expected to be blustery with patchy rain in the northeast of the country by the morning. There will be sunny spells and scattered showers elsewhere.
Overnight, rain will continue to affect parts of Ulster but it will be mainly dry elsewhere with clear spells. Cloud will thicken in the west towards dawn.
Temperatures will be between -2 to 3 degrees, with the east of the country being the coldest. Patches of frost are expected.
Wednesday will be warmer, with dry weather forecast for much of the country in the morning.
However, by the afternoon and into the evening, there will be countrywide rain, which will turn heavy at times.
Light easterly winds will back southeasterly and freshen ahead of the rain. Highest temperatures will be between 5 to 9 degrees.
Outbreaks of rain will linger in Ulster and Leinster overnight, with clearer conditions and scattered showers elsewhere. Lowest temperatures of 1 to 5 degrees and light breezes are expected.
Thursday will have a cloudy and largely dry start to the day, with light westerly winds. Later that day another spell of rain, which will be heavy at times, will come from the west.
On Thursday night there will be outbreaks of rain that are heavy at first but turn patchy later. Lows of 4 to 6 degrees in moderate southeasterly breezes.
The outlook for next weekend is for conditions to remain unsettled with rain at times.
