Key Takeaways:
- A severe heatwave is expected to hit New Zealand, with temperatures reaching up to 38C in some areas
- Heat alerts have been issued for several regions, including Hawke’s Bay, Nelson, and Marlborough
- Strong winds and heavy rain are also forecasted for some areas, with gusts of up to 130km/h expected in exposed parts of the Canterbury high country
- The fire risk is very high in southern Hawke’s Bay and Wairarapa, with a high risk of wildfires spreading rapidly
- People are urged to take precautions, including checking on vulnerable neighbors, keeping pets safe, and avoiding any activities that could start fires
Introduction to the Heatwave
The MetService has issued a warning for severe gale northwesterlies gusting 130 km/h in exposed places for the Canterbury high country and near the foothills from 10pm tonight and through tomorrow. Additionally, strong wind watches have been issued for the lower North Island and much of the remaining eastern and lower South Island. Heat alerts have also been made for many centres across both islands, with temperatures expected to reach up to 38C in some areas. The heatwave is expected to be particularly severe in Hawke’s Bay, with Hastings forecast to reach 38C tomorrow and Napier expected to reach 36C.
Fire Risk and Precautions
The fire risk is very high in southern Hawke’s Bay and Wairarapa, with a high risk of wildfires spreading rapidly. Pyatt urged people not to light any fires or do any spark or heat generating activities near vegetation, as 97% of wildfires in New Zealand are started by people. Any fires lit in the last two months should also be checked by raking through ashes and dousing in water if unsure. Under these extreme conditions, one spark can start a fire that will spread rapidly, be extremely difficult to control, and potentially cause significant damage. People are also urged to take precautions, including checking on vulnerable neighbors, keeping pets safe, and avoiding any activities that could start fires.
Weather Forecast
The forecast heat has captured the most attention, especially for Hawke’s Bay where Hastings’ forecast 38C tomorrow is 12.7C above the city’s January average. A high of 34C is expected today. Neighbouring Napier is forecast to reach 36C tomorrow, and 33C today. The South Island can also expect to swelter, with 31C expected in Blenheim and Kaikōura on Sunday. Christchurch is forecast to have highs of 31C on Saturday, rising to 32C the next day. Heavy rain warnings and watches are also in place for parts of the western and southern South Island this weekend. A strong wind watch is in place for the Marlborough area from 1-10am Sunday and in the Wellington and Wairarapa area from 2am Sunday to 4am Monday.
Causes of the Heatwave
The rising temperatures are because of a “big, warm, moist air mass” that is set to pass over the country after causing a heatwave and sparking large bushfires in Australia. This hot air mass has been over Australia for a little while, and while New Zealand won’t see the same extreme temperatures, it will still be pretty hot. The Earth Sciences seasonal climate outlook for January to March also indicated above-average rainfall for the north and east of the North Island, and below-average rainfall for the west of the South Island. A weak La Nina will be at play over New Zealand to start the year, which means more northerly and northeasterly winds, and more weather from the tropics, which is a warm place.
Long-term Climate Trends
The Earth Sciences’ latest annual climate report showed 2025 was New Zealand’s fourth-hottest year on record, with four of its five warmest years occurring since 2021. Most regions were hotter than average by between 0.51C and 1.2C, but parts of Northland and Bay of Plenty were significantly hotter, by more than 1.2C. The report also found that marine heatwave conditions, which are in play now, don’t turn off as quickly as air temperatures do. This means that New Zealand is starting off on a warmer note, with the climate already loaded with heat from previous years. As a result, the country can expect above-average temperatures, particularly in the north and west of the North Island, for the first few months of this year.