Photo: RNZ / Rebekah Parsons-King
Southerly winds are set to bring cooler temperatures to much of New Zealand on Friday and into the weekend.
It would be a big shock after summery highs were reached Thursday - Blenheim hit 29.5C and Ashburton 27C.
MetService meteorologist John Law told Morning Report the cooler weather will make its way up from Marlborough into Wellington and along the East Coast of the North Island throughout Friday.
"A real dramatic change yesterday, about 20C drop from Christchurch high yesterday to what we've got at the moment, around about 6C there (this morning).
"I think that difference is going to be much more noticeable after that warm day yesterday."
He said a change of wind direction meant cold air from the Southern Ocean was being pushed across the country.
"A real cold change last night" - MetService meteorologist John Law
Law warned the cold wet weather was expected to stick around throughout the weekend.
MetService has issued a Heavy Rain Watch for Hawke's Bay north of Napier and Tai Rāwhiti from Friday afternoon until Sunday.
"So it's worth keeping an eye on there."
And Wellington, eastern Marlborough Sounds and Kaikōura coast have a Strong Wind Watch for Friday afternoon and evening.
"Those southerlies set to pick up as we head through this afternoon as well and perhaps some stronger gusts there, perhaps even around about 90kilometres per hour, but that's going to add to those temperatures making it feel a fair bit cooler as well," Law said.
It follows a particularly wet and windy October and comes ahead of drought and fire fears this summer.
Law said spring is always a volatile time of the year and while the changing winds aren't a classic El Niño pattern, he expects that weather cycle to take over as summer nears.
Meanwhile, the Avalanche Advisory is warning of a moderate avalanche risk for alpine areas at Mount Aspiring, rising to high alpine terrain for Aoraki Mount Cook and Arthur's Pass.
It said the strong winds and rain meant lower freezing levels which could reduce the risk but that depended on the snow on Friday.