Winter 2012

A season of two halves: cold and dry, then wet and warm.

Temperature

The first half of winter was colder than usual; the second half of winter was unusually mild. Overall, winter temperatures were above average in the west and south of the South Island, as well as in Nelson, parts of Northland and around Ohakune. Elsewhere, winter temperatures were generally near average. 

Rainfall 

An extremely wet winter in the north and east of the South Island; unusually dry in the west and south of the South Island. Rainfall generally near normal in the North Island, except western Bay of Plenty and the Wairarapa coast, which were wetter than usual.

Sunshine

An unusually cloudy winter for Otago, south Canterbury, Nelson, Marlborough, and Wellington.  Extremely sunny in the west and south of the South Island. It was also a rather sunny winter for western parts of the North Island.

Soil moisture

As at the end of winter, below normal soil moisture levels for the southwest South Island. Above normal levels for the Kaikoura Coast and south Canterbury.

Overview

Winter was characterised by much higher pressures than normal to the southeast of New Zealand, and extending across the South Island. However, the season started off with frequent southwest winds over the country, resulting in a cooler and drier than normal start to the winter. In the middle of July, a change to more frequent northeast winds brought relatively mild and rather wet weather to many areas.

Winter was a season of two halves – it started colder than usual but ended unusually warm. Overall, it was a relatively mild winter in the west and south of the South Island, as well as in Nelson, parts of Northland, and around Ohakune (with winter temperatures between 0.5°C and 1.2°C above winter average). The change in pressure patterns mid-season meant that in all other regions winter temperatures were near average (within 0.5°C of the winter average). The nation-wide average temperature in winter 2012 was 8.7°C (0.4°C above the 1971-2000 winter average), using NIWA’s seven-station temperature series which begins in 1909.

It was an extremely wet winter for the north and east of the South Island, being the wettest winter on record for Timaru, and one of the wettest winters on record in the Nelson region. In contrast, it was one of the driest winters recorded in the west and south of the South Island. For the North Island, most regions recorded near normal winter rainfall (between 80 and 120 percent of winter normal rainfall total). Exceptions to this were the western Bay of Plenty and the Wairarapa coast, which were both much wetter than usual.

As at the end of winter, below normal soil moisture levels were evident across the southwest South Island. In contrast, above normal soil moisture levels were observed on the Kaikoura Coast and in south Canterbury.

It was an unusually cloudy winter for Otago, south Canterbury, Nelson, Marlborough, and Wellington. It was the cloudiest winter on record for Takaka. In contrast, it was an extremely sunny winter for the west and south of the South Island. It was also rather sunny over western parts of the North Island.  Record-breaking winter sunshine was experienced at Taumarunui, Cheviot, and Queenstown.

Further highlights:

  • The highest temperature was 22.7°C, observed at Christchurch on 26 August.
  • The lowest temperature was -11.8°C, at Darfield on 7 June.
  • The highest 1-day rainfall experienced was 358 mm at North Egmont on 16 July.
  • The highest gust recorded was 161 km/hr at Taiaroa Head on 28 June.
  • Of the six main centres in winter 2012, Auckland was the warmest and sunniest, Tauranga the wettest, Christchurch the coolest, Dunedin the driest, and Wellington the cloudiest.

Full report

Winter 2012 climate summary (PDF 577 KB)

For further information, please contact:

Ms Georgina Griffiths

Climate Scientist– NIWA National Climate Centre, Auckland

Tel. 09 375 4506 (office) or 027 293 6545 (mobile)

Dr Mike Revell

Principal Scientist, Meteorology and Remote Sensing, NIWA Wellington

Tel. 04 386 0328