There is still snow on Old Military Road and at Sally Gap in the Wicklow Mountains as well as heavy fog. "Extreme caution is advised," said the AA.
In the north, there are reports of black ice around Banbridge and Lurgan. Roads around Rathfriland are said to be treacherous and Drumnascamph Road, Laurencestown, is closed because road conditions are so bad.
Two vehicles stuck in the snow outside Kilfinane, Co Limerick. Cars sliding across the road @limerick_leader pic.twitter.com/C7s0gQ1fAu
— Áine Fitzgerald (@AineFitzgerald2) January 20, 2015
It will be a cold night, said Met Éireann, with tempratures down to -2.
There are going to be outbreaks of rain and sleet which will become more widespread and heavy in places with a possibility of isolated thunderstorms in parts of the northwest. There could be snow, mostly on higher ground.
Drier, clearer conditions are set to develop in west and northwest counties early in the night and will spread gradually eastwards overnight with frost and icy conditions developing in many areas.
Some showers will follow into western and northwestern areas.
Despite rising temperatures later in the week, the weather will edge towards being “less cold” rather than mild, according to Met Éireann.
On Friday a band of rain is set to cross the country as temperatures return to average for this time of year.