Kiwis were told tonight to reduce their electricity usage this evening while the country deals with a “winter-like surge” of unseasonably freezing temperatures.

But, it wasn’t to do with a lack of power, instead the warning to consumers was actually part of a “trial” from Electric Kiwi to “help us prioritise future ways for our customers to participate in peak demand events and save money while you’re at it”.

Snow is expected in the central North Island tonight as polar air plunges temperatures to below zero, and frosts are possible as far north as Auckland and Northland.

MetService has issued road snowfall warnings for four mountain passes in the South Island, with up to 5cm of snow likely to settle overnight.

Temperatures in Auckland, meanwhile, were forecast to drop to 6C overnight and fall to 4C tomorrow night. On Thursday, the high could reach 17C with fine conditions and cool southerly winds.

Frosts were likely around the country tomorrow and Friday morning. MetService attributed the cooler temperatures to a string of cold fronts sweeping the country with brisk southerly winds.

MetService meteorologist John Law said it was possible Auckland could have frosts, adding that clear night skies and cold winds created “perfect conditions” for cooler-than-average temperatures.

Regarding the North Island chill, Law said: “If you’re in Hawke’s Bay tomorrow and you look out at the hills to the west of you, you may see a dusting of snow.”

‘Turn off heaters and lights, delay charging electronic devices - the grid is facing potential tightness’

Electricity provider Electric Kiwi contacted its customers this evening asking them to voluntarily reduce their power usage.

The company said: “Electricity supply is tight tonight. The grid is facing potential tightness of electricity supply from 6pm-7.30pm.”

Transpower tonight said there was no risk to New Zealand’s electricity supply.

A spokesman for the state-owned power transmission company said they would communicate any issues to the public themselves.

“It is a cold night and demand is high,” he said.

”But we monitor [the grid] and if we thought there was a risk to electricity supply, we would be communicating that with the public.

”We’ve not done that in this case - it is Electric Kiwi operating off their own back.

”[We] assure New Zealanders that we will communicate with them if there is any risk to the public.”

It comes after Taumarunui started Wednesday at -4C and Taupō began the day at -2C. Further south, Christchurch residents woke to -3C, Timaru started at -2C and Queenstown saw -1C.

Niwa said this was a “fast start to the snowy season” and said Friday would be “a very cold day for the time of year”.

Some of the winds likely to buffet the country overnight tonight could reach 80km/h in exposed places in Westland. Gales were also possible around Wellington and Marlborough tomorrow morning.

The earliest road snowfall warning came into effect at 3pm today, for the Crown Range Rd. It was expected to end at 6pm today.

Lewis Pass, State Highway 7, Arthur’s Pass, SH73 and Porters Pass were under road snowfall warnings from 7pm today at the earliest to 3am on Thursday at the latest.

Flurries on the Crown Range Rd were recorded at 4pm today - prompting a caution from MetService to motorists to “drive safe and take care on the wet roads and poor visibility”.

MetService meteorologist Mmathapelo Makgabutlane said this May was in stark contrast to the same month last year.

“Many may recall the tropical-feeling temperatures of May 2023, where places like Auckland and Hamilton experienced record-breaking warm nights. However, this year, expect an overnight drop to mid-single digits in Auckland City and early-morning temperatures hovering near freezing in Hamilton,” Makgabutlane said.

Raphael Franks is an Auckland-based reporter who covers breaking news. He joined the Herald as a Te Rito cadet in 2022.

This article was originally published on the NZ Herald here.