Summer weather outlook: Niwa says it could be hotter, drier than average; hot temps for week ahead

New Zealand’s summer is shaping up to be hotter and drier than average, even with the long-range outlook putting a 50% chance of a weak and short-lived La Nina developing by the end of the year.

In the shorter term, some warm days are forecast for the coming week, with Auckland tipped to reach 22C by next weekend and some 26C temperatures around the central North Island on Thursday.

Auckland has a forecast high of 21C today, with isolated showers expected to turn to rain this evening and then clear overnight. Tomorrow should be fine with a 17C high.

Weather alerts have been issued for parts of the South Island for later today, with MetService putting a severe thunderstorm watch in place for Christchurch, the Canterbury Plains and North Otago from 1pm until 8pm.

Two strong wind watches are active for coastal parts of Dunedin and Clutha, and coastal Southland and Stewart Island from noon until 7pm today.

A southerly change will bring the threat for showers today, followed by cooler, and generally dry, conditions for tomorrow (Sunday). pic.twitter.com/lZz4QVDy5t

— NIWA Weather (@NiwaWeather) November 1, 2024

MetService meteorologist Oscar Shiviti told the Herald a front was pushing over New Zealand today and tomorrow, keeping temperatures down until the middle of the coming week.

“Behind that front today and tomorrow is a high-pressure system, and that will bring some fairly fine conditions,” Shiviti said.

“As the week goes on, we’re expecting temperatures to rise slightly. On Thursday, we expect areas like Masterton to hit 24C, Taumaranui as well.

“There are some quite warm areas in the South Island too, with Alexandra to hit 26C on Thursday.”

‘More widespread dry conditions than what is typical for La Nina’ - Niwa

The National Institute of Water and Atmospheric Research (Niwa) said there was just over a 50% chance La Nina would develop by the end of the year.

⚠️ Nov-Jan Seasonal Climate Outlook:

🌊 A La Niña Watch remains in effect

🌡️ Air temperatures are very likely to be above average across NZ

☂️ Most regions to see near normal to below normal rainfall

🌧️ Short and sharp rain events for parts of the NIhttps://t.co/uSwYz4irOi pic.twitter.com/SeiM0zfe5j

— NIWA Weather (@NiwaWeather) November 1, 2024

“However, this event is likely to be weak and short-lived and might stay below traditional La Nina thresholds,” Niwa’s outlook summary said.

“There are indications for more widespread dry conditions than what is typical for La Nina across much of New Zealand, especially at the beginning of the three-month outlook period [November-January].

“Rainfall is most likely to be near normal in the east of the North Island, and about equally likely to be near normal or below normal for all remaining regions of the country,” Niwa said.

There is an increased chance of more days above 25C than “normal” from November through January due to a potential prevalence of northeasterly winds, Niwa said.

However, La Nina-like conditions could bring short, intense rain events for the north of the North Island and eastern parts of both islands, Niwa said.

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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