The mercury in Invercargill today will punch well above its weight, the southern city cranking up the heat and topping the likes of Auckland, Tauranga, and Wellington.
MetService meteorologist Alwyn Bakker says their forecasting predicts temperatures will reach as high as 22C in the afternoon, with mostly fine weather.
Auckland isn't far behind, however, with temperatures there set to reach 21C and 23C in Hamilton.
And other than a heavy rain watch in place for Fiordland and Westland, set to start from noon today, the entire nation is set for a great day.
The temperature will sing a very similar tune tomorrow too, MetService forecasting warm, humid conditions for most of the country.
The mercury is set to skyrocket to a whopping 28C in Christchurch and Kaikoura on Sunday, and equally toasty temperatures as high as 26C for Hawke's Bay and Gisborne.
But the balmy conditions will be short-lived and some parts of the South Island will experience a drastic 15C drop in less than a day, plunging the region into winter.
The best weather is reserved for eastern coastal regions of both islands where warm temperatures will send the mercury rocketing up to nearly 30C.
As well as the high temperatures, Canterbury is also in line for strong winds on Sunday.
Monday would usher in a drastic change in temperatures in the south, which would have people reaching for their winter woollies overnight.
"From Sunday into Monday one of the places to see one of the biggest drops is Ashburton and Timaru," MetService meteorologist Mmathapelo Makgabutlane said yesterday.
"On Sunday they're expected to reach 27C and then on Monday their maximum is only 12C. It's a drop of 15C."
Whangārei: Morning low cloud. The odd shower until evening. Northerly breezes. High 22C, Low 14C.
Auckland: Morning low cloud lifting, then fine spells. Northeast breezes. 21C, 14C.
Tauranga: Morning low cloud lifting and fine spells increasing. Light winds. 20C, 14C.
Hamilton: Morning low cloud or fog lifting, then fine spells. Chance of an afternoon or evening shower. Light winds. 23C, 10C.
New Plymouth: Morning low cloud, with drizzle clearing this morning and fine spells developing. Then the odd afternoon or evening shower. Northerly breezes. 18C, 13C.
Napier: Fine with high cloud. Northeasterly breezes. 22C, 14C.
Wellington: Fine start, then cloud increasing in the afternoon and drizzle developing in the evening. Northerlies. 17C, 14C.
Christchurch: Morning cloud, then fine and warm. Northeasterlies developing in the afternoon. 23C, 11C.
Queenstown: Fine. Westerlies. 20C, 10C.
Dunedin: Fine and warm. Northerlies. 23C, 14C.
Invercargill: Fine, some morning cloud. Northwesterlies. 22C, 14C.