Tauranga has experienced one of its warmest winters, with temperatures being noticeably higher than normal.
A climate expert said the past three months had been among the warmest winters for New Zealand since records began in the mid-19th century.
Tauranga had an average temperature of 11.4C in June, 10.3C in July and 12.3C in August, the normal average temperatures are 10.9C, 10.3C and 10.5C respectively.
There has also been significantly less rainfall in July and August, and an eight-day dry spell in June.
Climate scientist Jim Salinger said September-like temperatures had been occurring throughout August.