Temperatures will plunge to freezing, with lows of -1C from Thursday through to Sunday.
WeatherWatch.co.nz said the very large low-pressure zone will engulf the country in this year’s first major winter storm.
“It is a significant weather event which will intensify on Thursday, peak on Saturday and Sunday, then ease into next week,” the forecaster said.
It would bring severe gales, heavy snow, downpours and a drop in temperatures nationwide.
The storm was now brewing in the Southern Ocean.
Ballie said the hills around Dunedin may also see some snow this weekend, but Christchurch won’t be in the firing line.
“Southland and, Dunedin, Saturday night and into Sunday, could see snow to quite low levels. There’s a very large cold pool moving over the region.”
Ballie said it’s probably the coldest storm we’ve seen this winter, and this would be a “good event” for southern ski resorts.
The north would not escape the polar blast with southerly winds ushering in the winter chill.
“The North Island is in for windy and certainly [in] the western, western and northern areas, it’s going to be very windy, and showery. We’ve had as you probably know, a lot of north easterlies, we’re now going into a south westerly flow and that south westerly flow is going to persist all the way through the weekend and there will be pulses of showers with that.”
From Thursday afternoon, and all the way through the weekend he said it was going to be “quite windy” and there’ll be quite a wind chill factor.
While maximum forecasts for Auckland would be in the order of 15 degrees, Ballie said it was not going to feel “anything like that”.
“It will feel somewhere in the range of six to 10 for most of the time.”
Meanwhile, startling images of the rural roads in Tairāwhiti after heavy rain lashed the region during the weekend have emerged.
Dr David Hall, of the Auckland University of Technology, posted images from his colleagues of the roads near Tolaga Bay to Twitter.
A local state of emergency was in place for Tairāwhiti as the severe weather closed major roads out of the region, forced residents to evacuate, and saw rivers burst banks.