Police in the Southern District are urging drivers to stay off the roads tonight if they can possibly do so.
There is a significant amount of black ice in several parts of the district, including Central Otago, Southland and Waitaki.
Police received reports of several crashes this afternoon where cars have slid off the road and rolled.
There were also numerous crashes around the district on Saturday as cars skidded on slick roads.
Fortunately none of today's crashes had resulted in serious injury, police said.
MetService advised caution driving on State Highway 94, SH90, SH8, SH80, SH93, SH6, SH98, SH85, SH87, SH6 and SH8 due to ice on the roads.
The warning echoes yesterday's call for people to stay indoors, with police saying it was unwise even to go walking or cycling as footpaths would be very slippery.
Motorists in Bay of Plenty are also being warned to take extra care on the roads.
Senior Sergeant Fane Troy, area manager for road policing, said bad weather would hit the region tonight.
"The roads are wet following rain today and temperatures are expected to plummet overnight.
"Please adjust your driving to the conditions, keep an eye on your speed and maintain your following distances."
But the ongoing warnings have not got through to everyone - a man was clocked driving at 179km/h on icy roads near Queenstown on Saturday afternoon. He was charged with dangerous driving.
Meanwhile in the North Island tonight a crash in Waikato has killed one person and left three injured.
The two-car crash happened on SH1 at Kinleith, near Tokoroa, just before 5pm.