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.
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.
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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