Those in the lower South Island will have woken up to freezing conditions, with temperatures falling below zero in parts of Otago.
MetService meteorologist Philippa Murdoch said it was -5C at Dunedin Airport about 6am today.
Queenstown got down to -4C and Alexandra -3C overnight.
And if you were looking forward to some fine weather for the long weekend, you'd better head south and keep on going.
But even then the rain or showers will catch up eventually.
The showers and milder winter temperatures that moved onto Northland yesterday - replacing the dying throes of a frosty, snowy autumn - look set to march southwards, although gradually.
"The South Island is looking mostly fine, probably pretty chilly this morning. But a few showers developing in the east," said Murdoch.
"In the North Island, however, it's a slightly different story. We've got a low approaching from the north. There are some heavy falls and possible thunderstorms in that."
A low-pressure system that has been gathering strength over the Tasman Sea is driving cold fronts over the North Island and squeezing out the high which delivered cold temperatures this week.
Auckland is forecast to start out cloudy today, with showers and strong to gale northeasterlies setting in by afternoon. Tomorrow brings rain, with the possibility of thunderstorms. Monday brings more rain.
The picture is similar on the Coromandel Peninsula and the Bay of Plenty, except the deterioration may be a bit later than in Auckland.
In Taupo, the rain is expected to hold off until tomorrow.
Wellington should be a bright spot today, enjoying some sun, but the some rain moves in there too from later tomorrow.
Christchurch is in for some showers off and on through the long weekend. But in Central Otago, the cold, frosty weather looks set to persist until the holiday is done.
NZTA is warning roads across the lower South Island may be slippery this morning due to ice.
Ice is expected on State Highway 8 between Alexandra and Raes Junction and at Lindis Pass, on SH6 between Kawarau Gorge and Gibbston and Kingston to Frankton, on SH94 between Te Anau Downs and Gulliver River Bridge and on SH73 between Springfield and Arthurs Pass.
Drivers should take extra care through these areas.
Delays of up to 20 minutes are likely from Murchison to Inangahua Junction on SH6 as maintenance crews carry out rock scaling work.
There's black ice on SH85 from Alexandra to Palmerston, SH8 Omarama to Twizel, SH87 Kyeburn to Mosgiel and SH94 Mossburn to Te Anau.
The northeasterly system moving onto Northland last night would progress down the North Island over the weekend, delivering quite a bit of rain and wind.
"Currently Northland is under watch for severe gale winds from 11am [today] and on watch for rain with periods of heavy rain starting 11pm [last night] to Sunday afternoon," , said Ravi Kandula, MetService meteorologist.
Those weather watch notices might be extended to Auckland and Coromandel this morning.
Sustained, strong northeasterlies were expected from Northland to Taupo and parts of eastern Bay of Plenty, Kandula said.
"It's a gradually moving system with strong winds and some heavy rain associated with it."
Auckland: Cloudy, then showers developing evening and northeast strengthening. 17C high
Hamilton: Cloud gradually increasing, then rain at night, easterlies and a high of 15C
Tauranga: Cloudy and few showers, more frequent from evening and easterly picking up. High of 16C
Wellington: Fine, apart from low cloud and drizzle around the Hutt Valley. Southeasterly breezes. 14 high
Christchurch: Mostly cloudy, a few showers. Easterly breezes developing afternoon. 11C high
Dunedin: Fine, morning frosts or fog. Northeasterly breezes. 11C high