Roads are closed throughout most of the central North Island as the cold snap delivers more snow, and access to Gisborne is difficult.
State Highway 1, the Desert Road, is closed and alternative routes via National Park and Taumarunui are also shut.
Motorists are advised to use State Highway 3 via New Plymouth.
The Napier-Taupo Road is closed, while roads both north and south of Gisborne are closed. This includes State Highway 2 between Bartletts and Morere and between Matawai and Otoko.
Heavy and frequent snow showers were predicted about northern Hawke's Bay and southern parts of Gisborne through to this morning.
The largest amounts of snow are expected about the hill country between Gisborne and Mohaka, where another 20cm to 40cm of snow may accumulate above 300m.
"This is a significant amount of snow, with total accumulations likely to approach a metre in some places above 500m," Gisborne Civil Defence Emergency Management said about 11pm last night.
Gisborne had the coldest day of winter yesterday and the hills around the East Coast had snow.
Gisborne locals are calling it the biggest fall of snow in about 30 years.
Highways are being reviewed later this morning and yesterday many did manage to open, though driving conditions remained treacherous.
Motorists are being told to delay all travel on central North Island roads.