Kiwis might get their first taste of summer on Thursday, with some places expected to get close to 30 degrees.
NIWA said an Australian heat blast will see temperatures surge and could even set a spring first.
So far, nowhere in New Zealand has reached 30 degrees this spring with Wairoa in Hawke's Bay the closest reaching 29.6C in September. The warmest place in October was Kaikōura reaching 29C and in November so far it was Christchurch when it reached 29.1C.
Allan Baillie from MetService told Newshub temperatures on Thursday, particularly in the South Island are going to be well above average.
Ballie said the Canterbury region is expected to be the pick of the bunch being nine degrees above average when it's expected to reach 28C.
Ashburton is also expected to be hot reaching 27C - eight degrees above average – and Blenheim should reach 28C – seven degrees above average.
He told Newshub this is because of strong north-westerly winds that are set to hit New Zealand.
"We've got an approaching front and ahead of that front, we're going to get strong north-westerly winds," Ballie explained.
"As those winds come over the mountains, they dry out and sink, as they sink back to sea level, they warm up and that's called the foehn effect."
But while Kiwis are expected to see hot weather on Thursday, the temperatures are set to plummet on Friday when a cold front hits New Zealand.
"All those eastern areas are going to be pretty warm, but they're going to suffer a very sharp temperature drop once that front comes through," he said.
"The maximums tomorrow [will be] in the high 20s but the minimums overnight, sixes and sevens, so it's going to drop by 20 degrees between the maximum late afternoon and the minimum overnight."
