Heat alerts possible as temperatures begin to soar

Source: Radio New Zealand

MetService says heat alerts could be issued as temperatures begin to soar on Wednesday.

Timaru is expected to hit 30° on Wednesday, while it’s set to be 28° in Dunedin and 29° in Christchurch.

The high temperatures are set to also run into Thursday, when Christchurch is tipped to hit 30°.

Is summer finally here?

You may want to keep your sunscreen handy as temperatures for the next couple of days will reach high 20’s and low 30’s

Keep an eye on our website as heat alert maybe issued

To find out more on heat alert: https://t.co/No53UJdu2a pic.twitter.com/s1lNQ9XWor

— MetService NZ (@MetService) November 25, 2025

Heat alerts are normally available from December through to February but conditions meant monitoring had started earlier this year, lead forecaster Chelsea Glue said.

“There are two things that can trigger a heat alert, the first is a one-off extreme high temperature for the maximum temperature for the day,” she said.

“The second is prolonged period of not quite so extreme, but still warm days and nights as well and it’s the second situation we might be finding ourselves in.”

Plenty of weather in the second half of the week

Rain and wind reach the South Island on Wed, with Heavy Rain Watches in the west. A stronger round follows on Thu with heavy rain, thunderstorms and strong winds likely

By Friday the focus shifts to the North Island, with… pic.twitter.com/mBv9kpniYC

— MetService NZ (@MetService) November 25, 2025

MetService first started issuing heat alerts in 2021, and last summer they covered 46 towns and cities.

Thresholds for triggering a heat alert vary from one region to another.

Glue said the temperatures coming on Wednesday and Thursday, caused by warm north-westerly winds, were higher than usual.

“They are on the more extreme end and that’s why there is the potential for triggering an alert to warn people it could be a lot warmer than you might expect for this time of the year,” she said.

MetService’s advice was for people to stay hydrated and in the shade and to check on any vulnerable people and animals.

Meanwhile, MetService is also predicting heavy rain for parts of the country.

A warning is in place for Tasman west of Takaka until 2pm.

There’s also a heavy rain watch for Buller until 2pm, and the Westland ranges until 11am.

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– Published by EveningReport.nz and AsiaPacificReport.nz, see: MIL OSI in partnership with Radio New Zealand