Many Dunedin people scraped ice from windscreens and trod carefully as the first significant frost of the year affected most of the city yesterday.
Dunedin Airport recorded -4degC about 6am. It caught some motorists unaware, and there were reports of vehicles slipping and sliding in the city.
Police reported three non-injury crashes due to ice.
The driver of a car which spun about 5.40am told police "it was very icy'', and another car spun and hit a bank about 7.12am as a result of "black ice'' on the northern motorway, a police spokesman said.
The third crash involved a vehicle slipping on ice and hitting a parked car in Serpentine Ave about 7.20am, he said.
MetService meteorologist Lisa Murray said Dunedin Airport was colder than Alexandra (3.1degC), Wanaka (-2degC) and Queenstown (-2.3degC) early yesterday, but Ranfurly hit -5degC.
There were colder places around the country but at higher altitudes, she said.
The forecast was for frosts in parts of Dunedin and Central Otago today but it would "not quite get to -4degC'' at Dunedin Airport.
People should keep an eye on a "significant low'' forecast for the weekend, which could bring snow to high country areas, Ms Murray said.
Police issued a statement yesterday morning advising drivers to exercise "extra caution'' due to wet weather and a drop in temperature producing frosts.
