A wintry blast of snow and freezing wind will follow the spring storm buffeting the country today, forecasters say.
Severe gales are expected to hit Wairarapa, Southland, Clutha and Dunedin this evening as a deep low over the south Tasman Sea passes up the country.
Meteorologist Daniel Corbett said the storms would be followed by a "major cold outbreak" over New Zealand from Tuesday morning.
It would batter the lower South Island with cold, showery and strong south-westerlies and bring snow to sea level, he said.
Snow was expected to fall down to 500 metres or lower in eastern areas from Gisborne to Canterbury, around the central North Island high country to Taranaki and southwards to Wellington.
"Wind chill will be a significant factor even in places where it doesn't snow," Mr Corbett said.
"The "feels like" temperature will be well below the actual temperature - partly because the air will be very cold for the time of year, but also because the winds are expected to be noticeably strong over a lot of the country."
Many North Island places were expected to continue to experience strong south-westerlies for the next few days.
Widespread frosts were likely anywhere south of Auckland on Wednesday, with severe frosts possible in inland parts of the South Island, MetService said.
Meanwhile, heavy rain is likely about Fiordland and Westland today, with significant spillover rain also possible in the headwaters of the Otago and Canterbury lakes and rivers.
MetService said periods of heavy rain is expected in Buller and northwest Nelson from this afternoon through to tomorrow morning.
Heavy rain about the ranges of the central North Island eased early this morning.
Snow falls are forecast on Arthurs Pass, Lindis Pass, Milford Road and Lewis Pass over the course of the day, clearing tomorrow.