Met Eireann has issued a Status Yellow low temperature warning for Donegal.
Lowest temperatures of -3 degrees Celsius are expected overnight.
The warning is valid from 2am on Sunday morning through until 10am.
The low temperature warning is for Leinster, Cavan, Monaghan and Donegal.
Met Eireann say exceptionally cold weather is forecast around the country for next week with significant wind chill and severe frosts. Disruptive snow showers are expected from Tuesday onwards, particularly in the east and southeast. Snow showers, perhaps merging into more persistent bands of snow, are forecast from midweek.