But a spell of calmer weather is forecast mid-week before the rain and wind return to the South Island by Thursday and Friday, according to MetService.
MetService meteorologist Mmathapelo Makgabutlane said the cold, showery southwesterly flow would continue into today, although the worst wind and rain would ease.
This morning frost was expected to be widespread across much of the South Island and the central and eastern North Island, while snow has closed the Desert Rd between Rangipo and Waiouru overnight.
Things are warmer further north - Auckland was sitting at a rainy 10C just before 6am, while Hamilton and Tauranga were both at 7C.
Wellington’s temperature was at 4.9C this morning while Christchurch has dropped below -2C, although the city had been forecast to start the day at -4C. The coldest spot in New Zealand is currently Mt Cook at -5.6C.
NZTA web camera view of the Desert Rd this morning.
Makgabutlane said Wednesday would be the week’s highlight with sunshine across the country, while the chill and possible frosts could reach Auckland and Northland by Thursday morning.
“A ridge of high pressure will bring settled weather and double-digit daytime temperatures for most regions. These milder temperatures will continue into the latter half of the week as a northwesterly flow develops ahead of an incoming weather system.
“Winds will increase over the South Island on Thursday, gradually spreading to the North Island by Friday. Wet weather is also expected to return to the western South Island on Thursday, with some rain making its way over the Southern Alps into inland Canterbury and Otago.
Goodbye lobe of the polar vortex.... hello, high pressure! 🌤️
An easing trend is forecast into the middle part of the week. It will be chilly, though!
The next front will likely move up the country from Friday into the weekend, bringing rain & milder temperatures... pic.twitter.com/I9qKy2gET6
“By the end of Friday, western parts of the North Island may also see rain, with the rest of the island likely to experience wet weather on Saturday.
“To go from snow to sunshine back to blustery winds all in a matter of days? It’s yo-yo weather at its finest.”
A new front is lining up New Zealand and looks set to move up the country from Friday, bringing more weekend rain.
Niwa said conditions would ease during the middle part of the week as the country farewells the polar vortex, but warned it would remain chilly.
Then, the next front will likely move up the country from Friday into the weekend, bringing rain and milder temperatures.
“There’s some uncertainty as to how quickly this front will move and at least some chance that it could stall out near the North Island later in the weekend,” the forecaster said in a post to social media.