Snow has fallen in the south and north overnight and motorists are being warned of more treacherous weather conditions, as a freezing winter blast makes its way from the Antarctic Ice Shelf.
Some flights have been cancelled at Queenstown, Dunedin and Invercargill Airports, and the Interislander ferry has canned all sailings across the Cook Strait with the massive swells expected to hit Wellington's coast.
Bluebridge is also throwing caution to the wind, cancelling sailings for Tuesday and Wednesday.
Those living near Wellington's coast are being asked to find alternative accommodation with the massive swells expected on Tuesday.
The full impact is due to push through on Tuesday evening with six-metre waves, MetService says.
Wellington Civil Defence says packing a bag with supplies is advised for people living near the coast, should things quickly take a turn for the worse.
"Updated modelling shows that the impacts from this event could be similar to the wave inundation that was experienced during the 2013 Matariki Storm," the Wellington region emergency management office said in a statement.
"People living close to swell and surf exposed coastlines should be prepared for the likely possibility of wave overtopping and flooding of roads, potential damage to property, deposition of debris, and driftwood, sand and gravel making access difficult or dangerous and possible road closures.
"If your home has been impacted by past swell and storm events or [you] have concerns, arrange accommodation with friends and family from Tuesday late afternoon to Wednesday afternoon."
There's also been a significant amount of snowfall around the central North and South Islands overnight with more expected throughout the day.
Road snow warnings are in place for Napier-Taupō, Desert, and Remutaka Hill Rds in the north, and the Lindis Pass, State Highway 1 between Dunedin and Waitati, and the Crown Range and Milford Rds in the south.
The NZ Transport Agency (NZTA) said on Monday night the road was closed between Dunedin and Waitati.
"Please delay your journey, as there is no detour available," Waka Kotahi NZTA said in a statement. "An update will be provided when the road status has changed."
Heavy snow watches are in place for Southland, Fiordland, the Canterbury Plains, the Tararua Range and Taihape, and strong wind watches have been issued for Fiordland, north Otago, Dunedin and Clutha, coastal Hawke's Bay, Wellington and the Marlborough Sounds.
