Temperatures are set to plummet to lows of minus three degrees tonight, with Met Éireann advising of "widespread frost and ice" overnight.
Conditions are expected to remain mostly dry with just a slight chance of an isolated rain or hail shower.
The national forecaster has said there will be an icy start to tomorrow with patches of freezing fog in places.
Very cold overnight, minimum air temperatures were below average at many stations🥶🌡️📉— Met Éireann (@MetEireann) December 7, 2022
Temperatures will continue to fall over the coming days so do take heed of warnings➡️https://t.co/daaKPKhgqn
and advice from ➡️https://t.co/GgyXeUDHhC pic.twitter.com/5vCGT1HLvX
There will be sunny spells and possibly some wintry showers pushing in from the north.
Maximum temperatures will range from just 0 to three degrees in light northwest or variable winds.
Bitter conditions will continue for the remainder of the week, according to the current national outlook.
Sub-zero temperatures by night will lead to "sharp to severe frost along with icy stretches" while temperatures by day will hover close to zero in most areas.
Some hail, sleet or snow showers is expected, but there will be a good deal of dry weather overall.
A countrywide winter weather advisory, issued on Sunday, remains in place until 9am on Monday.
Met Éireann has said it expects that further updates to the advisory and warnings will be made in the coming days.