Snow is to become more widespread across the country as the week moves on.
That's according to Met Éireann Forecaster Michelle Dillon, who was speaking as a Winter Weather Advisory is in place until Thursday.
An Arctic airflow will bring sharp to severe frosts and icy stretches on roads and footpaths.
There will also be some showers of hail, sleet and snow with the potential for freezing fog.
Michelle told Newstalk Breakfast winds will move the snow from the north and west.
"We'll have an arctic blast of air down over the country really for much of the week, up until Friday," she said.
"Very cold - we'll have sharp frost by night [with] temperatures down as low as -6 some of the nights - especially tonight and again on Wednesday night.
"We'll have some showers of hail, sleet and snow - a lot of dry weather actually today.
"Into this evening then we'll have sleet and snow moving into Kerry and west Cork.
Very cold overnight Sunday/Monday,very cold over the next few days and nights,with temps getting as low as -5C🥶🥶
Becoming milder from Thursday onwards. 🌡️📈
Min temps overnight ⬇️ pic.twitter.com/vqTWdbo0hJ— Met Éireann (@MetEireann) January 16, 2023
"We'll also have some sleet and snow showers in the north.
"Those sleet and snow showers become more widespread then as we go through tomorrow - in Ulster and Connacht mainly for a time.
"So we'd expect a little bit more in the way of sleet and snow becoming more widespread across the country into tomorrow night.
"Most widespread for the north and the west, but some will make their way down across the country in those freshening winds.
"Further sleet and snow showers into Wednesday, then it becomes drier on Thursday and then milder then through Friday."
The weekend will then turn milder "with outbreaks of rain at times," she added.