2020 was Aotearoa New Zealand’s 7th-warmest year on record. The nationwide average temperature for 2020, calculated using stations in NIWA’s seven-station temperature series which began in 1909, was 13.24°C (0.63°C above the 1981–2010 annual average). New Zealand’s hottest year on record remains 2016, when the nationwide average temperature was 13.45°C (0.84°C above the 1981–2010 annual average).
Based on the seven-station series, 2020 featured six months with above average temperatures (greater than +0.50°C of average), six months with near average temperatures (within -0.50°C to +0.50°C of average), and no months with below average temperatures (less than -0.50°C of average).
It has now been 47 months since New Zealand has had a month with below average temperatures (the last such month was January 2017). Furthermore, six of the past eight years have been amongst New Zealand’s hottest on record. This trend is consistent with the overall pattern of global warming.