Further south melting snow is now turning to ice on the Napier-Taupo highway as frigid temperatures continue to cause havoc on the North Island roads.
Temperatures dipped below zero overnight across both islands as New Zealand continued to shiver through its coldest spell this winter.
National Park village had the coldest night in the North Island on -4.1C, Hamilton dropped to -1.5C, Levin -1.1C and Rotorua -1C. Auckland was a chilly 4C.
MetService forecaster Derek Holland said most of the South Island recorded a sub-zero night, and Mt Cook Village dropped to -5.8C, Reefton to -5.3C and Blenheim -4.1C.
The day had started with a heavy frost in all regions.
Just one state highway remains closed but ice continues to make roads treacherous in central regions of the North Island.
The Napier-Taupo highway reopened at 11.30am after being closed for five days.
Hastings District Council said the Napier-Taupo Rd was now affected by melting snow turning to ice as temperatures stayed below zero.
The Waikato Civil Defence advised motorists travelling through the Karangahake Gorge this morning to be wary of ice.
This is the Napier-Taupo Rd - no wonder we can't get through. NZTA is advising that the small areas where the snow has...
Posted by Hastings District Council - Te Kaunihera ā-Rohe o Heretaunga on Sunday, 7 August 2016
The Waimana Gorge between Awakeri and Opotiki remained closed after a large slip blocked the road early yesterday.