Met Éireannn has issued a cold weather warning with temperatures predicted to fall as low as minus 4 degrees on Monday morning.
The warning is in place until midday.
Drivers should exercise caution and remember that stopping distances are ten times longer in snow and ice.
It will be very cold this morning with severe frost and icy stretches only slowly clearing in most areas and possibly lingering into the afternoon in some sheltered places.
It will be dry apart from the odd wintry shower in the north.
Frost will quickly set in again after dark.
Tonight will be cold at first, especially over the eastern half of the country with widespread frost and icy stretches on untreated surfaces.
However, cloud will thicken from the west and southerly winds will strengthen, clearing the frost later in the night. Rain or drizzle will develop in the west around dawn.
The met service said the changeable weather would continue, remaining cold through to midweek with frosty nights.
It said the weather would be less cold later in the week but it would also be wet and windy at times.
It said early indications suggested that daytime temperatures would recover to more normal values for Friday and the weekend.
Night time temperatures would vary more and would be low enough in places for some frost.