Met Éireann has issued a status yellow weather warning for 22 counties ahead of a drop in overnight temperatures.
The meteorological service advises that it will be very cold tonight, with temperatures falling to as low as minus four degrees Celcius.
There will be widespread severe frost and a risk of icy patches in areas. There is a possibility of a few shallow fog patches inland.
After a very cold start tomorrow, frost will clear and temperatures will recover to range six to nine degrees Celcius by the afternoon.
The warning affects counties Cavan, Monaghan, Donegal, Carlow, Kildare, Kilkenny, Laois, Longford, Louth, Offaly, Westmeath, Meath, Clare, Cork, Kerry, Limerick and Tipperary as well as all of Connacht.
It is in place from 8pm tonight until 9am tomorrow.