Niwa climate scientist Gregor Macara said the nationwide average temperature in January was 18.38degC — 1.16degC above the 1991-2020 January average — making it the country’s 10th warmest summer on record.
And while many places in the North Island smashed records for its extreme amounts of rainfall, Otago and Southland did the same for its lack of rainfall.
Invercargill (24mm), Balclutha (6mm) and Nugget Point (12mm) had their lowest January rainfall on record; while Mt Cook Airport (46mm), Wānaka (4mm) and Manapouri’s West Arm Jetty (60mm) recorded their second-lowest amount of January rainfall.
"It was exceptionally dry for parts of western and southern Southland, coastal South Otago, northwestern Otago, Banks Peninsula and Aoraki/Mt Cook Village, which each received less than 20% of normal January rainfall."
Mr Macara said the prevalence of high pressure over the South Island contributed to relatively high sunshine hours.
Alexandra recorded 305 hours of sunshine, making it the town’s sunniest January since records began in 1930.
Both Alexandra and Cromwell recorded the highest temperatures in the country, reaching 34.2degC at the end of January.
Franz Josef recorded its highest mean air temperature for January with 19.1degC — 3.9degC above average.
Recording their second-highest were Haast (18.3degC), Milford Sound (17.9degC), Secretary Island (18.6degC), Te Anau (17.4degC), Manapouri’s West Arm Jetty (17.7degC), and Oban on Stewart Island (15.6degC).
It was particularly warm for western parts of the South Island, with temperature anomalies exceeding 3.0degC in many locations.
Mr Macara said La Nina persisted during January and was a key climate driver for the month.