Rotorua police are warning motorists of icy conditions in the area, in particular State Highway 5 south of Rotorua and also north of the city to Tirau.
The temperature at 7.30am this morning was 3.6C, though the MetService said it felt like -1C.
Meanwhile, snow has closed the Napier-Taupo highway,
the Desert Rd and State Highway 1 from Waiouru to Hunterville.
Nationwide, predicted chaos on the roads overnight failed to materialise as the polar blast dumped snow and ice across the country but forecasters are predicting problems with severe frosts over the next couple of days as temperatures plummet.
The polar blast gripping the country abated overnight. Police in Invercargill, Dunedin and Christchurch reported no problems on the roads, where snow and ice had turned to slush.
However, a number of roads in the higher parts of the South Island were closed and police were still warning motorists to take care.
In Wellington city overnight rain cleared the roads and all buses were running this morning, after services to some hill suburbs were cancelled last night.
However, the Rimutaka Hill and Paekakariki Hill roads were still closed by snow, as were State Highway 2 between Muriwai and Morere, south of Gisborne, and SH1 at Hunterville and the Desert Rd to Taihape, and SH5 between Napier and Taupo.
MetService meteorologist Dan Corbett told Radio NZ frost would be an issue over the next couple of days as the country was now exposed to cold, polar southerly winds.
"Our next problem will be over the next couple of nights as the skies do clear and the high settles in and the winds go light, allowing temperatures to radiate away and drop away at night, will be the very strong severe frosts."
Strong winds during the day would be bitterly cold,
"It will feel raw, if you ever wondered how it would feel in the Southern Ocean in a boat in the winter."
Dunedin, Queenstown, Christchurch and Wellington airports were all operating this morning, however they warned there could be delays on some flights.
Christchurch lines company Orion last night said power has been restored to all but 40 customers in the rural areas south and south-west of Christchurch tonight, while around 100 were without power around Christchurch city. Orion was working to restore these but many would have been without power overnight.
Canterbury and Lincoln universities said they would reopen today.
Wellington Electricity said about 85 customers lost power in Whiteman's Valley near Upper Hutt overnight and in the Akatarawas from about 1.30am.
Customers were warned they could experience problems with low hot water levels as the load was controlled.
- additional reporting NZPA