NZ Transport Agency Waka Kotahi advised of the first closures - on State Highway 8 from Twizel to Fairlie and SH80 from Pukaki to Mt Cook - about 6.15pm.
The closures, owing to forecast ice and snow, start from 8pm today and are scheduled through to 8am tomorrow, though their reopening is weather-dependent, NZTA says.
In an update at 7.15pm NZTA said SH73 (Porters Pass) was closed just before 7pm because of ice and snow, while on the West Coast, SH6 was closed between Ross and Hari Hari after strong winds brought trees down.
The news comes after snow fell on the Crown Range and in parts of Otago today, prompting warnings for motorists to be "sensible" and prepared for widespread disruptions.
Weather warnings were in place for much of the South today but by this evening most had been lifted.
Heavy snow warnings were lifted late this morning. Up to 35cm of snow was earlier forecast to settle in parts of inland eastern Otago.
State Highway 85 between Kyeburn and Palmerston closed just before 9am today due to snow but reopened at 12.55pm.
The Lindis Pass, between Omarama and Tarras on SH8, was catching snow but remained open, with electronic signs warning drivers of the need to take care and slow down, NZTA said.
HEAVY SNOW FOR CANTERBURY
The heaviest snow has now shifted northwards, with warnings in place for Canterbury from about midday today for the North and South Canterbury high country regions, and the foothills about and south of the Rangitata River.
MetService has extended several snowfall warnings for a number of South Island highways, RNZ reported.
Up to 60cm of snow was expected to settle on SH73 at Porters Pass through until 9pm tomorrow, with more to fall higher up.
In Arthur's Pass (SH73), up to 10cm of snow was expected to settle near the summit, through until 6pm tomorrow.
In Lewis Pass (SH7), between 8cm and 15cm of snow was expected to fall on the road before 11pm tomorrow.
The Mt Cook/Aoraki highway (SH80) from the base of Lake Pukaki/the SH8 intersection to Mt Cook Village was closed this morning but had reopened by early afternoon. It will close again overnight.
SH8 from Fairlie through Burkes Pass to Tekapo reopened before midday, and Tekapo to Pukaki was open again after 11am.
Snow blanketed the summit of the Crown Range, linking Queenstown and Wānaka, this morning and chains must be fitted if driving this alpine road.
A Queenstown Lakes District Council spokeswoman said more snow was expected throughout the day and road users were asked to follow crew instructions at checkpoints.
Elsewhere, the roads are wet and temperatures were reasonably warm and sitting above zero about 7am.
"This will likely change and there's a good chance the roads will get icy later in the morning. Expect a few rocks on the road if heading through the Kawarau Gorge."
In Central Otago, wet roads were being reported across the district with some strong wind gusts. A spokeswoman for the district council said there had been sleet and snow flurries in Manuherekia and Maniototo areas but it was not settling yet.
Danseys Pass Road is closed (from the gates past the Danseys Pass Hotel), due to snow and ice on the Waitaki side.
The Milford Road (SH94) in Southland remained open.
NO SNOW IN DUNEDIN
A heavy snowfall warning of up to 25cm warning had been place earlier today for SH1, from Dunedin to Waitati, but was lifted late morning. Just 1 to 2cm of snow was now expected settle on the road above 300 metres until 5pm.
There was no snow on the Northern Motorway, Three Mile Hill or other higher roads in the city from early today.
However, cold and slippery conditions meant road users should take care coming in and out of Dunedin over the Leith Saddle on SH1, particularly in the mornings, the NZ Transport Agency said this afternoon.
There was slushy snow at Clark’s Junction this morning but State Highway 87 remained open.
A Dunedin City Council spokesman said staff and contractors were out for much of yesterday and overnight making preparations for the bad weather. This included checking stormwater systems, sweeping gutters and clearing mud tanks.
"Residents can also help by checking nearby mud-tank grates for any debris and clearing them if they are able. We’re also asking everyone to take extra care on our roads, as the heavy rain may cause surface flooding and slips and can make driving hazardous."
Travel disruption and damage to trees and powerlines was possible, and cold conditions may cause stress for livestock. Residents were urged to prepare for snow, cold temperatures and possible power outages.
Momona dairy farmer Hamish Jenkins said he was confident the rivers and grounds around his farm would be able to take a heavy onslaught of rain thanks to one of the driest winters he had ever seen.
"It’s been so dry for so long, we haven’t had decent rain for months - the ground is so hard underfoot night now I think it could take a bucketing down of rain."
He said despite the possibility of it all being a "non-event", there was still a warning in place and farmers should still prepare. That included having enough feed on hand and preparing shelter for livestock.
"If rain falls as forecast, rivers are likely to be contained to their channels, but the situation can change rapidly.
"Rivers will be fast-moving, and conditions can change quickly, so it’s important people stay informed and be prepared."
- additional reporting ODT Online and RNZ
