Drizzle forecast for entire country, heavy showers in Auckland amid sudden 10C drop in temps

Drizzle is forecast across the country today, with heavy showers possible in Auckland, squally thunderstorms in the south, and a dramatic drop in temperatures bringing frost for some.
The polar jet stream is pulling a series of cold air surges across New Zealand today, on Sunday and early next week, the National Institute of Water and Atmospheric Research (Niwa) said.
Snow was forecast to fall around the Southern Alps last night, with up to 30cm expected to settle in some places. MetService-issued road snowfall warnings on five mountain passes will lapse by 3pm today.
A strong wind watch is also in place for Dunedin, Clutha, Southland and Stewart Island, where speeds could reach severe gales. MetService said there was a moderate chance this weather alert could be upgraded to a warning before.
The polar jet stream will make a comeback over the next 10 days with not one, not two, but three surges of cold, Southern Ocean air! 🐧The chill will be noticeable by Wednesday, followed by a reinforcing shot on Sunday & early next week.Snow will fly in the South Island ❄️ pic.twitter.com/26U6f2XIpx
Meanwhile, in Auckland, MetService forecast a mostly cloudy day with a few showers.
Rain could become heavy before fine spells take over in the afternoon. The city should reach a high of 17C before dipping to 10C overnight.
Thursday is expected to be mainly fine, with the chance of a morning shower. Rain should return on Friday before turning mainly fine again on Saturday, and giving way to rain again on Sunday and Monday.
MetService has also forecast showers and squally thunderstorms in Christchurch this evening. The city will have a bout of weather whiplash when temperatures drop almost 10C from its warmer-than-average 21C high yesterday to 12C on Thursday.
Hastings and Napier will also plummet from above-average temperatures to below-average.
❄️🗻Snow is expected for elevated inland South Island regions tonight into Wednesday🛻🚙Take care if you’ll be traveling on high-level roads and mountain passes, as several Road Snowfall Warnings are in placeDetails at: https://t.co/qHyE5zzql5 pic.twitter.com/JCUVdD1vIc
MetService said the plunging temperatures would mean frost for some parts of the country on Friday morning.
But Christchurch’s temperatures should bounce back again on Friday, reaching 18C and lasting until Sunday, when it is forecast to fall again when more heavy rain sets in.
There is a similar pattern across the country.
Storm-ravaged Dunedin should have sunny conditions on Thursday and Friday, and showers from Saturday and into next week.
Niwa has warned of potential downpours throughout October amid an emerging “La Nina-like” pressure pattern raising the odds of big rain events.
As part of Niwa’s October-December climate outlook, the seasonal forecaster has said more northeasterly winds would develop, there would be fewer westerlies, and this would contribute to above-average temperatures.
Raphael Franks is an Auckland-based reporter who covers breaking news. He joined the Herald as a Te Rito cadet in 2022.
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