People should wrap up warm and brace themselves for snow this weekend - bringing to an end a spell of fine, calm weather over most of the country.
The coldest of the air, which would come from near or even over Antarctica, would nick the lower South Island on Sunday, with snow falling to a few hundred metres, WeatherWatch.co.nz forecasters said.
The Catlins region would be most exposed to the coldest weather, with snow falling to low levels there. Rain and showers would push into Southland, the West Coast and Otago on Saturday turning to snow above a few hundred metres overnight Saturday and into Sunday with sleet and possibly the odd flurry to sea level.
Weatherwatch said the cold, wet weather would head north on Sunday, with showers across central, western and northern regions of the country.
Eastern areas will be mostly dry, with little rain for places such as Christchurch, Wellington, Napier and Gisborne.