Motorists are being advised to drive with care this afternoon despite a slight thaw on some routes.
Roads in the midlands, southwest and northwest are still said to be in a dangerous condition.
Met Éireann said rain and sleet will move north later and may fall as snow in mountainous areas.
Temperatures will fall below zero again tonight.
Gardai are advising motorists to avoid the areas of the Sally Gap, Glenmalure and Aughavanna in Wicklow, due to dangerous road conditions.
All emergency services have no access to these areas and people are advised not to travel there.
"We're continuing to urge motorists to take extra care," said Ronan Gilligan, AA Roadwatch.
Although conditions have improved greatly around Dublin caution is still required on secondary routes, Mr Gilligan said.
Elsewhere, conditions were said to be icy on the Abbeyleix-Carlow road between Abbeyleix and the quarry in Spink, and in Westmeath on the Mullingar-Rochefortbridge road and the Athlone-Mount Temple road.