The national weather service said it should be reasonably rain-free with the odd shower and southwest winds.
Mr Duncan said the cold air moving off the Antarctic ice shelves meant this weekend would feel like winter in Otago and Southland. "We'll see snow probably in Queenstown and down in Cromwell and sleet in Invercargill - it's kind of weird for November."
He said the worst of the frosty weather system should have moved off the country by tomorrow afternoon, but the cold air would linger.
The east of New Zealand, from Canterbury to the Coromandel, should have "pretty mild" temperatures, but most of the country would definitely be cooler than it had been.
Mr Duncan said it was also likely to be very windy this weekend.
"We've had it pretty mild for the last few weeks, so this will probably be a surprise for most people."
But the good news was it should start to warm up again on Sunday as the cold fronts moved off and it should be warm "wherever you are".