Photo: Supplied / Earth Sciences NZ
2025 was the country's fourth-hottest year on record, according to Earth Sciences New Zealand's (ESNZ) annual climate report.
The report found that most regions were hotter than average by between 0.51 and 1.20 degrees, but parts of Northland and Bay of Plenty were significantly hotter, by more than 1.2 degrees.
Leigh, North of Auckland, recorded the highest annual average temperature across the mainland 17.7 degrees, followed by Kaitaia at 17.1, and Whangaparāoa at 16.9.
The highest air temperature of the year was 35.6 degrees recorded at Kawerau on 7 December. This was followed by 33.8 degrees at Napier on 8 December, and 33.7 degrees at Ettrick on 16 February.
Photo: Supplied / Earth Sciences NZ
The report points out: "Of the six main centres in 2025, Auckland was the warmest, Tauranga was the sunniest and wettest, Christchurch was the equal-coolest, and Dunedin was the driest, equal-coolest, and least sunny."
The organisation has recorded the annual temperature at seven weather stations across the country since 1909. The report found a nationwide average temperature of 13.51 degrees.
Four of the five warmest years on record have occurred since 2021 as a result of human-induced climate change, it says.
Atmospheric carbon dioxide levels continued to rise, surpassing 423 ppm at ESNZ's Baring Head monitoring station during the year.
November was the warmest on record, with most of the country more than 1.2 degrees warmer than average.
Photo: Supplied / Earth Sciences NZ
Some regions were also much wetter than usual, with several areas of the South Island including Nelson, Marlborough and Banks peninsula receiving 20 to almost 50 percent more rain than usual.
According to the analysis, the soil moisture level was below normal for most of the North Island and the northern part of the South for the first quarter of 2025. Soil moisture is a key indicator of droughts and is watched by farmers. By the end of winter moisture was mostly back to normal but dried out in some eastern parts through to the end of November.
The crown for the region with the highest annual sunshine went to Taranaki with 2743 hours recorded at New Plymouth. It was followed by the Nelson region (2672 hours recorded at Richmond).
Photo: Supplied / Earth Sciences NZ
Sea temperatures were also on the rise.
Local sea surface temperatures were "relatively warm", says the report and remained pretty much above normal for the year, though there brief cooler patches west of the North Island.
"Most notably New Zealand observed its warmest (sea surface temperatures) November and 5th-warmest April on record."
Earth Science New Zealand Manager of Climate, Atmosphere and Hazards Nava Fedaeff. Photo: RNZ / Paris Ibell
Manager of Climate, Atmosphere and Hazards Nava Fedaeff said she hoped decisionmakers take note of the data.
She had worked at Earth Sciences New Zealand (formerly for NIWA) for more than 10 years, and every year it was the same message, she said.
During that time, there had been no locations that had experienced a record, or near record cold year.
"It's not just a blip. We've had 10 years back-to-back of extreme warmth, and I'm hoping this kind of information can be of use to decision makers.
"It's certainly not a great trend."
It was clear greenhouse gasses were contributing to the changes annual weather locally and globally, Fedaeff said.
"The announcement for the global rankings has not been made yet. but it's expected to be the either the second or third warmest year globally."
She pointed to the UK and Australia, which have also recently recorded some of their hottest years on record.
Photo: Supplied / Earth Sciences NZ
Among the report's other findings were:
- The highest confirmed wind gust for 2025 was 252km/h at Cape Turnagain on the east coast of the North Island on 21 October
- The coldest air temperature was at Mt Cook airport on 8 June 8 - -12.9C. The same day Lake Tekapo was -11.2C
- The wettest location, according to rain gauges, was Cropp River at the Waterfall (on the West Coast and about 975m). It recorded 10,951mm; another gauge on the Cropp River at Cropp Hut was just behind with 9925mm
- The highest temperature was recorded in December, which is uncommon for New Zealand. The last time this happened was 2015. It was 35.6C at Kawerau on 7 December. The next day Napier recorded 33.6C.
Sign up for Ngā Pitopito Kōrero, a daily newsletter curated by our editors and delivered straight to your inbox every weekday.
