Fifth-Warmest Autumn On Record Brings Wet Weather To The South Island
Autumn 2025 was characterised by higher than normal mean sea level pressure (MSLP) over and surrounding Aotearoa New Zealand. There were more northeasterly winds than normal over the country, resulting in above average (0.51-1.20°C above average) to well above average (>1.20°C above average) seasonal temperatures in every region of the country. Near average (±0.50°C of average) seasonal temperatures were limited to several isolated locations, namely Christchurch, Rangiora, Waiau, Masterton, Stratford, and Tūrangi. Overall, the nationwide average temperature for autumn 2025 was 14.5°C. This was 1.0°C above the 1991-2020 average from NIWA's seven station temperature series which begins in 1909, making it New Zealand's 5th-warmest autumn on record.
It was a wet season for eastern and northern parts of the South Island, with above normal (120-149% of normal) or well above normal (>149% of normal) rainfall for northern parts of Otago, eastern Canterbury, Marlborough, Nelson, and Tasman. Rainfall was also above normal or well above normal in Northland, parts of Auckland, Coromandel Peninsula, western Bay of Plenty, and parts of Wellington. In contrast, rainfall was below normal (50-79% of normal) in Dunedin, Aotearoa New Zealand Climate Summary: Autumn 2025 Issued: 5 June 2025 Whanganui, the Tararua District, and Hawke's Bay, with well below normal rainfall (<50% of normal) in Middlemarch.
One of the most significant events during the season was a heavy rainfall event over Canterbury from 30 April – 1 May. This resulted in considerable surface flooding, and saw a state of emergency declared in Christchurch, Selwyn District, and Banks Peninsula. Earlier in the season, the arrival of ex-tropical cyclone Tam on 16 April brought high-impact weather to northern parts of the country.
Thousands of people lost power due to downed power lines, while storm surges caused coastal erosion in some areas. See the Highlights and extreme events section below for more details of these and other notable weather events that occurred during the season.
Further highlights:
• The highest temperature was 33.6°C, observed at Timaru on 17 March.
• The lowest temperature was -5.0°C, observed at Manapouri on 19 May and Tūrangi on 22 May.
• The highest 1-day rainfall was 290 mm, recorded at Tākaka on 3 April.
• The highest wind gust was 200 km/h, observed at Cape Turnagain on 30 May.
• The sunniest four locations in 2025 so far are Taranaki (1257 hours), Bay of Plenty (1196 hours), Auckland (1182 hours) and Mackenzie Basin (1158 hours).
• Of the six main centres in autumn 2025, Auckland was the warmest, Christchurch was the coolest, Tauranga was the wettest and sunniest, and Dunedin was the driest and least sunny.
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