Winter lacked an Antarctic chill this year in New Zealand, to record effect.

Scientists said on Tuesday that the South Pacific nation had its warmest winter since record-keeping began more than a century ago.

The average nationwide temperature was 9.5C (49.1F) for June, July and August, about 1.2C above average and 0.3C above the previous record set in 1984, the National Institute of Water and Atmospheric Research said. Record-keeping began in 1909.

This year's unusually balmy winter was fuelled by a pattern of warmer winds from the north coupled with fewer of the southerly winds that typically bring cold air from Antarctica, Niwa climate scientist Brett Mullan said. Mullan believes that while global weather remain variable, it is warming.

The mild winter was a boon for farmers, who have been recovering from a punishing summer drought as it allowed grass to sprout in parched fields.

Nor did the warmer climate cause problems for New Zealand's skiers.

Annah Dowsett, a spokeswoman for the Whakapapa and Turoa ski fields on Mount Ruapehu, said dumps of snow early in the ski season followed by weeks of pleasant weather provided the perfect conditions.

She said the fields hosted above-average numbers of skiers throughout winter and Turoa went for an unusually long stretch of 46 days without needing to close once for inclement weather.

"It's certainly been pleasant," she said. "August is usually windy and snowy and cold."