Prime Minister John Key is expecting employers to take "a generous view" towards staff who are unable to make it into work because of problems caused by the polar blast battering most of the country.
"For the most part, most employees are hard working, they try and turn up to work when they can. I'm sure for the vast bulk they actually will,"he said.
"But if there's a whole lot of snow and ice and you can't get out of your driveway, then you'd expect employers to take a generous view towards that," he said.
Mr Key's call followed claims some employers were threatening not to pay workers who failed to arrive at work.
He also encouraged people to keep an eye on their neighbours, family and friends and particularly the elderly.
Police are continuing to warn that roads in many areas remain treacherous as snow and ice refreeze and become black ice.
"Adjust your speed and following distances accordingly, and take note of any reduced speed limits throughout the region," Sergeant Peter Theobald of police central communications said.
Police dealt with a series of minor crashes during the morning, but no serious injuries were reported.
Many state highways remain closed, including the Desert Road and Rimutaka Hill road in the North Island and the Lewis Pass and Arthurs Pass in the South Island.
St John regional operations manager for the South Island, Chris Haines, said emergency services had to tend to a few people injured from falling over in snow or ice today, while Wellington's Civil Defence controller Mike Mendonca encouraged people to slip a pair of thick socks over their shoes to avoid falling.
The Ministry of Education said it was up to individual schools to decide whether to open today, and a number in Wellington's western and hill suburbs decided to close.
Freezing conditions have also made it especially hard for homeless people to cope.
Wellington night shelter manager Mike Leon said demand for a warm bed jumped 50 percent last night.
"We're still coping though, but we could always do with some more blankets," he said.
Wellington City Mission manager head Michelle Branney told NZPA that more people were visiting its drop-in centre to warm up. Demand for a hot breakfast was also up.
Snow and ice also disrupted mail deliveries for a second day running across large parts of the country.
"Road closures and icy conditions have created some unavoidable delays," NZ Post spokesman Michael Tull said
The national power grid was also struggling under the burden of snow, ice and thunderstorms.
Grid operator Transpower's chief executive, Patrick Strange, said the weather was the worst he had seen for a long time -- and was causing a few headaches.
"We have crews out in this weather doing everything they can to prevent further damage to lines and subsequent power outages. It's a serious situation but we're confident we can manage it."
Lines company Powerco said staff had repaired the majority of yesterday's storm damage and restored supply to most customers, after falling trees and branches had torn down overhead lines, causing power cuts to more than 20,000 homes across the lower North Island.
This morning there were still about 350 properties without power in South Taranaki, rural Wanganui, Manawatu and Wairarapa.
About 1000 customers in rural central Canterbury, in areas including Rakaia, West Melton, Leeston and Greendale were without power overnight.
Electricity network Orion general manager commercial Rob Jamieson said the company was expecting to make real progress reconnecting the majority of affected customers from early this afternoon.
Around 450 homes in Upper Hutt were also without power this morning.
Both Lincoln and Canterbury University announced they would be closed today.
Airports in Christchurch and Queenstown were closed early this morning, but have since reopened. Some flights are operating out of Dunedin.
All city buses in Christchurch were cancelled for the day.
Access to Christchurch's CBD red zone remained closed today to all but essential services.
Fonterra's collection tankers were trying to get through to more farms today, after more than 1700 farms around the country were not reached yesterday.
"There are still some restrictions on milk collection throughout the South Island, but we have trucks on the road," a Fonterra spokeswoman said.
Farmers didn't necessarily have to dump their milk, as it was still early in the season and a lot of farmers were not at capacity yet, she said.
The cold conditions are expected to continue until Thursday, with significant snowfalls expected for southern and eastern parts of the South Island, and southern and central parts of the North Island, but are not predicted to continue down to sea level.
