Forecasters are predicting a "significant cold break" could bring a fresh dumping of snow across the country, with both main islands in the firing line.
MetService says chilly south to southwest winds are expected to bring snow down to low levels across most parts of the South Island on Sunday and the lower North Island on Monday.
That comes after a broad low-pressure system is forecast to move east across central and northern New Zealand on Friday bringing a brief period of heavy rain to western areas. Southwest gales are also possible in Northland, Auckland and Coromandel Peninsula.
"Disturbed westerlies affect the country on Saturday and there is low confidence of westerly gales becoming severe over the Tararua District and Hawke's Bay south of Hastings," a spokesperson said.
On Sunday a complex low pressure system is forecast to move east across central New Zealand, followed by cold and strong south to southwest winds.
"This weather system is forecast to bring periods of heavy rain across the central districts. There is low confidence of warning amounts of rain in Westland, Buller, northwest Nelson on Sunday, and in Canterbury north of Christchurch, Marlborough including the Sounds, Wellington and Wairarapa on Sunday and Monday."
There is also a chance of south to southwest gales becoming severe in exposed parts of coastal Clutha, Dunedin, Buller and northwest Nelson as well as in exposed parts of Canterbury north of Christchurch, Marlborough including the Sounds, Wellington, and Wairarapa on Sunday and Monday.
Forecaster WeatherWatch says the warmer weather many have felt for this time of year will change this weekend.
"But at the same time, the lower South Island will be getting a wintry change already arriving with temperatures dropping and some snow flurries to low levels later in the day or overnight."
Snow to around 100m to 200m is most likely to fall in Otago and Southland, while Canterbury looks to have snow chances around 200m.
The spokesperson said there is a possibility of a few sea-level snow flurries as well overnight on Sunday with low accumulation.
"Snow totals don't look too intense for low levels, as the current snow map suggests, but 50 to 70cm or more is possible in the mountains."
The cold air moves into the North Island by Sunday with snow likely in the Remutaka Ranges and into the Hawke's Bay ranges.
Early estimates suggest that flurries may go down to 300 or 400m in the North Island, they said.
