Police say the Napier-Taupo road will remain closed until further notice, after hundred of drivers were forced to abandon their vehicles following an unseasonal heavy snowfall two nights ago.
This afternoon police said the highway would stay closed until all abandoned cars had been removed.
More than 700 people were evacuated after their cars became stuck in metre-deep snow on State Highway 5 on Sunday night.
They were put up in emergency shelters set up in Taupo and Napier.
New Zealand Transport Agency national state highways manager David Bates said road crews had been aware that snow was forecast for the region, but were caught out when a large amount fell in such a short time.
"It was a freak occurrence which was significantly worse than we anticipated for this time of year," he told The Dominion Post.
"We had the equipment and crews to keep the road open as long as we could but a massive temperature drop around 2pm swamped our trucks and equipment."
The icy blast also cut power to about 400 rural properties between Hawke's Bay and Taupo, leaving farmers unable to milk cows.
The cold weather has also wiped out hundreds of newborn lambs in the central North Island and farmers have been urged to ensure lambs, and their mothers, had access to shelter.
MetService forecasters said light snow showers were expected in the area until this afternoon.