"It's going to be hot, some areas will be really hot this weekend," Mr Duncan said.
"I define spring as winter fading out and hints of summer coming in. Now that we've gone past the halfway mark of spring we're going to see more of the summer and less of the winter. In fact, this cold snap that we've just had will be one of the last ones."
He said this spring had been "pretty mixed up" weather-wise but December should see warmer, drier weather.
The only rain on the radar was a weak front expected to bring wet weather to Fiordland, Westland and possibly Southland on Sunday, he said.
"We're not yet seeing the end of the 'rainmakers'...but I think we're also going to start to see a drying out pattern over much of the country," Mr Duncan said.
MetService meteorologist Lisa Murray said a ridge of high pressure was bringing the fine spell.
Auckland would see blue skies with the "odd bit of cloud" at the weekend and the settled weather should hang around into early next week with a few showers possible, she said.
A trough approaching the South Island on Saturday was expected to bring a small amount of rain.
"Today we have a nice ridge of high pressure straddling the country and this remains into tomorrow as well," Ms Murray said.
"Much of the country should be fine, bits of cloud here and there...Fiordland will get a bit of rain tomorrow and into the evening but that's about it, really."
Brief rain was expected in the South Island as the trough moved north but it would ease by the time it reached Palmerston North, she said.
Ms Murray said it had been a pretty cool November on the whole.
"Usually in November it's getting warmer, leading into summer so we do get some really mild [ones].
"It's not that unusual, we have had snow events in November in the past, but it is a particularly cool one compared to some Novembers in the past."
The El Nino weather pattern increased odds of a drier-than-normal summer, which New Zealand had seen so far with many areas struggling with drought, she said.
In New Zealand, the ocean-driven El Nino system typically brings cooler, wetter conditions with higher rainfall to regions that are normally wet and often drought to areas that are usually dry.
***
The weekend's forecast:
*Whangarei: Saturday is fine with southerly breezes. High 21C, low 11C. Sunday will be mainly fine. High 21C, low 11C.
*Auckland: Fine on Saturday with southerly breezes. High 20C, low 11C. Another fine day on Sunday. High 19C, low 12C.
*Hamilton: Fine and light winds on Saturday. High 22C, low 6C. Mainly fine on Sunday with southwesterly breezes. High 21C, low 8C.
*Tauranga: Saturday will be fine with light winds. High 22C, low 9C. Fine again on Sunday. High 23C, low 10C.
*Wellington: Mostly fine on Saturday with morning and evening cloud. High 15C, low 10C. Sunday will be fine with northerlies freshening. High 16C, low 11C.
*Christchurch: Cloudy periods and northeasterlies developing on Saturday. High 20C, low 7C. Sunday will see high cloud and spots of rain. High 20C, low 10C.
*Dunedin: Saturday is mostly cloudy with chance of brief evening rain. High 16C, low 10C. High cloud on Sunday with light winds. High 16C, low 10C.
*Queenstown: Cloudy periods with chance of brief evening rain on Saturday. High 18C, low 9C. Few spots of rain on Sunday. High 19C, low 10C.
(Source: MetService)
