Motorists have been urged to drive carefully today as dangerous road conditions persist throughout the country.
Severe frost overnight has left any roads treacherous, while there is freezing fog in many areas.
AA Roadwatch said some road temperatures were as low as -6.5 degrees earlier today.
Rain throughout the country is adding to poor conditions, and several crashes have been reported.
Conditions on the N9 between Waterford and Ballyhale are treacherous, while gardaí advise avoiding driving in Navan, Athboy and Bective unless absolutely necessary.
The Wicklow and Sally Gaps remain impassable, and icy conditions remain around Clare, Limerick, Galway and Cork. Mayo County Council said gritting on roads around the county will resume tomorrow.
Met Éireann is predicting rain, sleet and snow spreading across the country by this afternoon, with temperatures rising from below freezing this morning to between 3 and 6 degrees celcius this afternoon.
The cold snap is expected to ease tonight, with temperatures between 0 and 3 degrees celcius.
While nearly all main roads have been gritted, drivers are being urged to drive cautiously and to allow for 10 times the usual braking distance.