A mild thaw today offered a temporary reprieve from the severe weather that has hit the country, but temperatures are expected to plunge again overnight.
Latest weather and travel updates
Some parts of the country will see temperatures as low as -6C.
The cold weather is showing no sign of abating, with freezing day-time temperatures set to continue until at least Thursday of next week.
Snow and ice melted in some areas today, but freezing fog and black ice are expected to cause problems in many areas tonight.
Gardaí are warning motorists to drive with care.
Households in some parts of the country, particularly in counties Cork, Galway and Meath, are being asked to conserve water.
