Schools across west Otago are closed as blizzard-like conditions buffet the south of the country.
Pupils at Tapanui, Heriot and Waikoikoi Schools and Blue Mountain College have been told to stay home today with buses unable to operate in the wintry conditions.
Two Tapanui preschools are also shut due to the deteriorating conditions.
Snow has already fallen down to 200m in some parts of Otago and Southland with forecasters warning it is likely to continue blanketing isolated eastern areas until evening.
Tapanui resident Chanelle Purser travelled through snow this morning to reach her office about 50km from home before turning round fearing she wouldn't be able to get back later today.
"My husband had to take me to work this morning in blizzard-like conditions," said the NZME sales manager.
She said conditions on the roads were becoming treacherous in the west Otago region and many drivers were giving up on their journey and returning home.
A video posted on Twitter shows snow whipped by strong winds before dawn. Further along, stretches of highway are under water from heavy overnight rain.
Much of the island's lower eastern coast is smothered in snow showers this morning, making driving hazardous and closing roads.
The MetService has issued snowfall warnings for several state highways, including in the Lindis Pass and State Highway 1 north of Dunedin.
Duty meteorologist April Clark said a front across the coast of Timaru to Westport was bringing heavy showers as well as snow.
Up to 2cm of snow is expected as low as 200m in certain areas, including Southland and Clutha. However given it was a southwesterly flow, it wouldn't be as heavy on South Island ski fields.
"They're probably not going to get the hugest dump from this one. It hits more on the eastern coast," said Clark.
The front was moving fast so conditions would ease this afternoon, she said, as the front moved north and tapered off.
"We have had reports of snow to 200m about 1cm to 2cm but it will be brief and the snow level will rise and it will turn into slushy showers. It will be on and off and it's not going to be solid rain."
The lowest urban temperature overnight was in Waiouru with -1.9C, and Timaru had -1.7C. Mt Hutt summit, at 2069m, recorded the country's coldest temperature with -7C.
Auckland experienced a balmy 8C overnight, Hamilton 3.2C, Tauranga 6.1C, Wellington 6.6C, Christchurch 1.2C, Dunedin 4.7C - 0.2C at the airport - and Invercargill dropped to 3.1C.
Clark said North Island temperatures should be similar tonight, thanks to cloudy skies, but would drop markedly in the South Island. Alexandra is forecast to get to -3C, and Wanaka -3.4C.
"Christchurch might not get quite as cold as inland areas including the McKenzie Country and inland Central Otago. They will get very cold tonight."
Another trough will hit the country about Thursday but it was still too soon to know what that would hold for the weekend. However, a high was about to push on to the country tomorrow bringing more settled conditions.
Meanwhile, snow and ice has closed SH85 between Kyeburn and Palmerston and SH94 Hollyford Valley Rd Intersection to Chasm Stream Bridge.
There is ice on SH6 Gibbston to Frankton, SH6 Kingston to Frankton, and there is snow on SH85 between Ranfurly and Alexandra. Road users are asked to take extra care.
There is also snow on SH8 in the Lindis Pass, SH93 Clinton to Mataura, SH8 Twizel to Fairlie, and there is snow and ice on SH80 between Aoraki Mt Cook and Ben Ohau.
Slips have come down on SH1 between the Hundalees and Kaikoura and the road has been closed between Pekata and Goose Bay.