Severe frost and icy roads will persist late tonight and overnight in many areas.
Gardaí and the AA are advising against unnecessary travel due to hazardous conditions.
Drivers are being advised to take extra care on all routes but especially on secondary roads which may not have been gritted. These are treacherous in many parts.
The Wicklow and Sally gaps are impassable due to snow.
Northern parts of Cork city are especially icy as is the Blarney-Ballincollig road.
There is also severe ice on the M7 near Portlaoise and on the N3 outside Navan and Kells.
Dangerous conditions are also reported on several parts of the N5 Westport to Longford Road.
Most Bus Éireann services are operating, albeit with delays, but a small number have been cancelled.
