“It may well be getting close to 30C ... so we’ll be keeping a close eye on that,” MetService forecaster Dan Corrigan said of Hawke’s Bay’s outlook.
Those temperatures would prove the warmest for spring so far, beating the 28.4C recorded in Christchurch on October 23.
A maximum of 25C is meanwhile forecast for Masterton on Thursday; while further north, Gisborne is expected to get a run of days reaching 26C from Friday.
It’s a similar story in the east of the South Island: Christchurch’s temperatures will hover around the mid-20s from Thursday to Saturday.
“Thursday afternoon will be a particularly warm one for eastern parts of the South Island,” Corrigan said.
“Ashburton is forecasting a high of 27C then, which is 9C above its average daytime high for November.”
Other centres in line for unusual November highs include Dannevirke (22C on Friday), Whanganui (24C on Friday and Saturday), Invercargill (23C on Thursday) and Alexandra (26C on Thursday).
Corrigan explained the big driver behind the late-week warmth: a northerly wind flow sweeping down on to New Zealand and over the main ranges of both islands.
“As that air descends across the mountains, that’s what’s going to produce those somewhat higher-than-normal early November temperatures in eastern places.”
But the unseasonable heat was book-ended by bouts of unsettled weather around the country – starting with a front moving up the South Island today and likely to bring showery conditions over parts of the North Island tomorrow.
“Central parts of New Zealand are likely to see some rain on Wednesday – that’s from southern Waikato down to Wellington and Nelson – but then, for most places, weather is expected to be dry for the rest of the week,” Corrigan said.
“Our next real weather-bringer is going to be a front that arrives in the lower South Island on Friday morning – that’s going to bring a change to slightly cooler temperatures for a while in Southland and Dunedin.
“But it will likely just be a brief, south-west flick for the bottom of the South Island going into the weekend and doesn’t look like it will have much of an effect on the north.”
Jamie Morton is a specialist in science and environmental reporting. He joined the Herald in 2011 and writes about everything from conservation and climate change to natural hazards and new technology.
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