Winter weather: Temperatures below freezing, more frost on way, MetService says

One main centre has woken to -3C this morning, and cold, frosty days are forecast for the rest of the week across New Zealand, with clear, settled conditions.

“A high-pressure system over the country is keeping that settled weather. It will mean clear days,” MetService meteorologist Oscar Shiviti said.

Even Auckland had some frosts in sheltered places this morning, and more were possible tomorrow morning, he said.

But the City of Sails was expected to be “relatively warm” with daily highs between 13C and 16C throughout the week. Tonight’s overnight low was expected to drop to 4C.

Christchurch woke to -3.8C today, Ashburton was on -1C, Timaru -2C and Blenheim -1C. The Garden City had a forecast of some high cloud today and a high of 11C.

Taumarunui dropped to -4C this morning and Taupō to -2C. Auckland was on 6C this morning.

MetService said it was Christchurch’s coldest temperature of the month. Taumarunui’s temperature was its coldest of the year so far.

The cold temperatures were due to the high-pressure system, Shiviti told the Herald.

“The coldest temperatures should be around Otago, Southland," he said.

Good morning Aotearoa New Zealand

❄🌫It’s a chilly start to the week for many, with frost or fog in some areas. At 7am, temperatures were still in the single digits in most places.

🌡🥶Christchurch hit -3.8°C, its coldest July temperature this year.
Taumarunui dropped to… pic.twitter.com/YcusLflaA0

— MetService (@MetService) July 20, 2025

“There has not been an opportunity for a lot of mixing [of air]. It is expected to remain over the country for the week,” he said.

“There is a chance of a shower around parts of the East Coast, around Gisborne and the Hawke’s Bay.”

MetService forecasts a partly cloudy day for Napier today, with a few showers around midday. Tomorrow should turn mainly fine apart from a shower in the afternoon.

Gisborne has a forecast of mostly cloud with some showers. Tomorrow should be mostly fine with some showers later in the day.

A southerly front is due to hit the country from about Wednesday; radar maps show a wall of rain hitting the East Coast.

“The front is part of the same high-pressure system, and it will mean showers for parts of the east throughout the week,” Shiviti said.

The frosty conditions prompted the New Zealand Transport Agency to issue a warning for motorists driving the Haast Pass yesterday afternoon.

“Due to black ice, take extra care when travelling,” the transport agency said.

Raphael Franks is an Auckland-based reporter who covers business, breaking news and local stories from Tāmaki Makaurau. He joined the Herald as a Te Rito cadet in 2022.

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