Wild weather couldn’t dampen a mega-weekend of live music in Auckland as thousands of keen concertgoers braved wet conditions on Saturday night. And the humidity that continued through Sunday is set to stay in many parts this week.

“A humid northerly flow is set to continue to impact Auckland throughout the whole week and leave many people feeling like we are in February or March-like heat. The week’s average temperature will sit around 25 degrees,” said MetService forecaster Gerard Bellam.

Those warm temperatures apply across New Zealand - with highs in the mid-20s across northern and central North Island. Wellington and Christchurch are set for highs of 20C, while the mercury will reach just 17C in Dunedin.

Bellam said it would be mainly fine in Auckland on Monday after showers cleared before dawn.

“There is a chance of a late afternoon or early evening shower, southerlies will develop in the morning and ease in the evening. It’s looking to be mostly fine on Tuesday with northeasterlies continuing. Rain will develop on Wednesday and see isolated showers for the remainder of the week,” Bellam said.

“Apart from the humidity, there are no major dramas on the weather front for the rest of the week. We are forecasting the lowest average temperature to be 17 degrees.”

Bellam said he was alerted to a brief tornado in Westport around 3pm on Sunday afternoon, with one witness saying she had seen her car move.

The debris-strewn garden of Litia Wild in Westport after a tornado struck today. Photo / Supplied

NIWA reported that belts of humid weather would be more common this summer due to the ocean-atmosphere phenomenon La Niña.

Traditionally, La Niña has delivered more north-easterly winds that bring rainy conditions to North Island’s northeast, and drier conditions to the south and south-west of the South Island.

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Thanks to the north-easterly winds, warmer temperatures also tended to play out over much of the country during La Niña, although there are always regional and seasonal exceptions.

NIWA said La Niña is creating warm seas in the southwest Pacific which are causing rising air and storminess, weather which is expected to sometimes reach while in a La Niña state.

This is the third time that New Zealand has seen a La Niña summer in as many years, dubbed by meteorologists as a “triple dip” – which has only ever been observed over 1973 to 1975, and most recently from 1998 to 2000.

Main centre forecasts

Auckland

High of 24C, low of 15C

Showers clearing before dawn, then mainly fine. Chance of a late afternoon or early evening shower. Southerlies developing morning, easing evening.

Wellington

High of 20C, low of 13C

Fine, apart from a possible shower north of Wellington Harbour before dawn. Northerlies, dying out this evening.

Christchurch

High of 20C, low of 13C

Mostly cloudy, morning low cloud and possible drizzle, but long fine spells in afternoon. Light winds, northeasterlies developing in the afternoon.

Dunedin

High of 17C, low of 14C

Mostly cloudy, possible morning drizzle. Some afternoon fine breaks. Light winds, easterlies developing in the afternoon.

Tauranga High of 23C, low of 17C

Showers clearing in the morning and fine breaks developing. Light winds and afternoon northerlies.

Hamilton

High of 25C, low of 13C

Showers clearing before dawn with morning fog possible, then becoming fine. Chance of an evening shower. Light winds.

National Short-Range Forecast

Northland, Auckland and Waikato

Morning cloud then mainly fine, with isolated showers this afternoon and evening.

Coromandel, Bay of Plenty and Taupo, also Gisborne and Hawke’s Bay

Fine spells. Isolated showers, some heavy, with possible thunderstorms about eastern Bay of Plenty and Gisborne.

Waitomo to Wellington, including Taihape, also Wairarapa

Generally fine. Areas of cloud and the odd shower in the west this morning.

Nelson and Marlborough

Mostly fine. Isolated showers inland this afternoon and evening, possibly heavy.

Buller and Westland

Scattered showers, becoming confined to the ranges this afternoon and fine spells developing.

Canterbury, Otago and Southland, also Fiordland

Areas of cloud or fog at first this morning, with some patchy drizzle about Canterbury and Otago. Mostly fine this afternoon, with isolated showers inland, some maybe heavy.

Chatham Islands

Cloudy with occasional rain.