Parts of the country will experience sub zero temperatures tonight with frost and fog.
AA Roadwatch has urged motorists to drive with particular care in counties Cavan, Clare, Donegal, Longford and Tipperary.
While main roads have been treated, drivers are urged to watch out for black ice.
Met Éireann says widespread snow showers will continue tonight and will rise to several centimetres in places. It says very strong northerly winds will bring blizzards.
A gale warning has been issued for all Irish coasts.
