Hawke’s Bay’s twin cities record hottest spring in 135 years – experts warn of ‘new normal’

Napier’s weather station by Nelson Park recorded the city’s highest mean air temperature for spring with 16.4C, a 2.5C departure from normal since records began in 1870.The weather station by Napier Airport recorded its fourth-highest mean air temperature with 15.7C, a 2C departure from normal.Dannevirke had a record 14.1C mean spring air temperature, a 2.4C departure from normal since records began in 1951Takapau Plains hit its record mean temperature for spring with 13C, a 1.9C departure from normal since records began in 1962.Wairoa had its third-highest mean air temperature since records began in 1964 with 15.8C, a 1.8C departure from normal.Whakatū’s spring mean air temperature was 15C, a 2.3C departure from normal since records began in 1982.

The nationwide average temperature in spring 2025 was 13.5C.

This was 1.3C above the 1991-2020 spring average, making it New Zealand’s warmest spring since Earth Sciences NZ’s seven station temperature series began in 1909.

La Nina was officially declared by Earth Sciences NZ in October.

This usually brings frequent northeasterlies, but westerlies and occasional warm northerlies continued to keep temperatures near record highs in November.

Earth Sciences New Zealand meteorologist Chester Lampkin said the primary driver of the hot spring in Hawke’s Bay had been northwesterly, downslope winds across the region.

“When wind slopes down the ranges, it warms and dries out, leading to usually warm/hot and dry conditions for Hawke’s Bay.

“The westerly winds all spring-long were quite strong, partially because of a sudden stratospheric warming (SSW) event.

“Additionally, New Zealand as a whole has been warmer than usual due to the aforementioned northwesterly wind flow, again, partially due to the SSW, and marine heatwave conditions across our waters.”

Lampkin said when there’s warm water surrounding land, it led to overall warmer weather as the wind flowed over the already warm water.

When asked if warmer seasons like spring are the new normal, Lampkin said he was a meteorologist, not a climate scientist, but did expect warmer-than-normal weather to continue to occur more often in a warming climate.

“It’s going to be another warm, hot summer, and that certainly points to a new normal,” Lampkin told RNZ.

“That’s not to say cold weather cannot or will not happen, but warmer seasons are more likely to occur because of global climate changes.”

After an incredibly hot start to summer, the warm air mass that’s been sitting over the majority of the North Island has now been replaced by a new high-pressure system moving in from the west.

MetService meteorologist Alec Holden said that system was promoting southerly winds.

“Which is like a good shower at the end of the day, washing off this murky, sweaty air mass and pushing it out into the Pacific, leaving us with something a bit more pleasant.”

Holden said to expect clear skies from Saturday afternoon through to Monday with milder temperatures in the 20s in Hawke’s Bay before potential rain hits in the middle of next week.

Jack Riddell is a multimedia journalist with Hawke’s Bay Today and has worked in radio and media in the UK, Germany, and New Zealand.