A late rush of hail and snow has seen Dunedin's streets slow to a halt as people navigate the ice.
Minor crashes have been reported around Dunedin, including a crash in Heriot Row and London St where a car crashed into a parked vehicle.
State Highway 1 between Leith Valley and Waitati has been closed.
Callers have reported backed up traffic on the Southern Motorway and Three-Mile Hill.
The Otago Regional Council has suspended all Dunedin bus services due to dangerous driving conditions.