Temperatures are expected to reach as low as -5 degrees in some areas this evening as the bad weather returns to the country.
Snowfalls of up to 10cm are also possible over the coming days, according to Met Éireann.
Drivers have been advised to take care when on the road, particularly tomorrow morning when conditions are expected to be treacherous.
Met Éireann said it is likely to be very cold this evening with a widespread severe frost leading to icy roads and pockets of fog by tomorrow morning. This will be replaced by wet and windy weather developing along the south coast which is expected to move up over much of Munster and Leinster during the day, falling as sleet or snow in many places.
Sleet and snow are also expected over parts of Ulster and Connacht for much of tomorrow night before clearing northwards.
"There's an active system in the mid-Atlantic at the moment which will certainly cause added disruption in Britain through Friday and possibly Saturday and that will probably pass by the south of Ireland too," said Met Éireann forecaster Vincent O'Shea. "We think it will primarily affect Munster, the midlands and Leinster and as it pushes inland on Friday there's a high risk that there will be large snowfalls, particularly in areas above 200m," he added.
Mr O'Shea said while temperatures will remain low over the weekend it would be mostly dry, with a return to mild weather expected next week.
A spokesman for the National Roads Authority said there were sufficient salt supplies available to local authorities. Seán O'Neill said the authority had more than 40,000 tonnes of salt in the country with 8,000 tonnes arriving in Foynes earlier this week. He said further supplies are expected in the coming days.
