Severe weather warnings are in place for about two thirds of the country, with areas expected to be hit by either gale-force winds or snow.
The areas concerned are Auckland, Great Barrier Island, Waikato, Waitomo, Coromandel Peninsula, Bay of Plenty, Rotorua, Taumarunui, Taupo, Taihape, Gisborne, Hawke's Bay, Tararua, Wairarapa, Taranaki, Wanganui, Manawatu, Kapiti-Horowhenua, Wellington, Clutha, Central Otago and the Southern Lakes.
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It was a case of westerly gales about the North Island, easing by the morning, and heavy snow about the lower South Island late overnight and into Sunday, the MetService said.
Snow would fall to low levels in Fiordland and Southland, and also about Taumarunui and Taihape, it said.
Here's why the Crown Range is closed. MetService is predicting lots more snow to come. pic.twitter.com/u52wFFLFlD
— QLDC (@QueenstownLakes) July 29, 2016
The South Island's alpine passes were expected to experience heavy snowfall, particularly around the summits, and blizzard conditions were likely in exposed areas.
Drivers will need chains when travelling along SH6 (Haast Pass), SH7 (Lewis Pass and Rahu Saddle) and SH73 (Arthurs Pass).
The avalanche risk is keeping the Milford Road closed.
The Queensland Lakes District Council said the Crown Range Road would stay closed overnight, and would be reassessed at 7am.
Wind gusts were expected to reach 130km/h in central Hawke's Bay and Tararua District, which would be strong enough to lift roofs and make driving conditions hazardous.
A severe weather watch was in place for the possibility of severe westerly gales developing for the rest of the North Island, from Auckland southwards.
MetService said people in those areas should keep up-to-date with the latest forecasts in case the watch was upgraded to a warning.