September was the warmest September on record, Niwa says, and vegetable producers say access to water will be a key consideration over the months ahead. Niwa said the national average temperature last month was 11.9C, 1.3C above the 1991-to-2020 September average and the warmest since the seven-station temperature series began in 1909. A period of exceptionally high temperatures for early spring were recorded on September 20 and 21 including a maximum temperature of 29.6°C in Wairoa, which is the highest September temperature on record for the North Island. Of the main centres Auckland was the warmest, Tauranga the sunniest, Dunedin the driest, Wellington the wettest and least sunny, and Christchurch the coolest.