Icy roads in sheltered areas will be a potential danger for motorists tonight as temperatures are set to plunge.
Higher ground in Dublin, the Wicklow mountains and other parts of the east will be hit hardest by plummeting temperatures.
Temperatures falling to -3C, or even -4C on higher ground, will hit the eastern part of Ireland but it will not be as cold further west.
Met Eireann forecaster Eoin Sherlock said it will be a dry night tonight which will mean frost will not be as widespread nor as severe as earlier feared.
Rain that is expected to clear off by this afternoon may not have a chance to dry off before temperatures dip considerably after dark. Roads where there is standing water or where it remains wet pose a black-ice danger.
Clear skies will ensure it is a cold night because there will be no clouds to bounce back any upward radiating heat, Mr Sherlock indicated.
Ice, frost and fog will clear slowly during Sunday morning and the day will be cold and bright, with sunny spells. A few showers are possible, but most places will be dry. Top temperatures will range from 6C to 10 C.
The weather in the coming days will be "a mixed bag", Mr Sherlock said.
Met Eireann are forecasting Sunday night to be cool with a mixture of clear spells and cloudy periods with lowest temperatures 1C to 5C.
It will be mild and breezy on Monday. Some sunny spells, but cloudy periods also, with scattered patches of drizzle. Highs of 9C to 11C, are expected. It will be mild and windy overnight.