October 2006

Rainfall: Well above normal in Auckland, Wairarapa, Manawatu, and near Christchurch; below normal in Central and East Otago Significant soil moisture deficits continue in North and Central Otago; deficits developing in other eastern regions Wind: Much windier than average over the South Island and southern North Island Temperature: Average or below average in all regions Sunshine: Very sunny inland South Canterbury, East Otago, and Southland
October was another month of climate extremes. It was windier than usual over most of the South Island and southern half of the North Island.

28 February 2007
  • Rainfall: Well above normal in Auckland, Wairarapa, Manawatu, and near Christchurch; below normal in Central and East Otago
  • Significant soil moisture deficits continue in North and Central Otago; deficits developing in other eastern regions
  • Wind: Much windier than average over the South Island and southern North Island
  • Temperature: Average or below average in all regions
  • Sunshine: Very sunny inland South Canterbury, East Otago, and Southland

October was another month of climate extremes. It was windier than usual over most of the South Island and southern half of the North Island. In fact, several locations in Marlborough and Otago recorded their windiest October in over a decade. It was also very wet in Auckland, Wairarapa, and Manawatu, while significant soil moisture deficits persisted in Otago. On 13 October, föhn northwesterlies produced a near record one-day heat-wave for October, with maximum temperatures between 28°C and 30°C occurring in many eastern locations from Gisborne to Otago. Rainfall for the month was about 200 percent (twice) of normal in Auckland, Wairarapa, Manawatu, and just south of Christchurch, the very wet weather resulting in very saturated soils in Manawatu and Wairarapa. Rainfall was just over 50 percent (half) of normal in East Otago. Below normal rainfall in the southern South Island resulted in continued significant soil moisture deficits (110-130 mm) in parts of North and Central Otago. Soil moisture deficits, although not yet major, also exist in South Canterbury, Marlborough, and central Hawke’s Bay. The national average temperature of 11.9°C was 0.3°C below normal. However, October was much cooler than usual in parts of King Country, coastal Wairarapa, and Wellington. Sunshine hours were above normal in much of the south and east of the South Island, but below normal in the west of the North Island from Auckland to Wellington. More anticyclones (‘highs’) predominated over the southeast of Australia and the Tasman Sea, with below average pressures southeast of New Zealand. This pattern produced more frequent southwesterlies than normal over New Zealand, and many more days than average with strong winds over the South Island and the southern North Island. The southwesterlies were interspersed with some significant southerly storms, notably on the 4th-6th, and the 23rd-25th.

Other Highlights

  • The highest temperature during October 2006 was 30.4°C recorded at Gisborne Airport on the 13th.
  • The lowest air temperature for the month was -5.1°C recorded at Middlemarch on the 5th.
  • Severe weather on 1 October produced high winds, attributed to tornadoes or waterspouts, which damaged trees and property in West Auckland. Heavy rainfall and widespread surface flooding occurred on the same day in parts of Auckland City.
  • Southerly gales and high seas resulted in Cook Strait ferry sailings being cancelled for much of the day on the 4th, and overnight into the 5th. These conditions also affected rail and air travel. Surface flooding occurred in parts of Wairarapa, with some large landslips in the region. Heavy snowfall occurred in the Gisborne and Hawke’s Bay high country on the 6th, as well as the North Island’s Desert Road.
  • A wind gust of 176 km/h from the northwest was recorded at Castlepoint on the 19th.
  • More southerly gales occurred through Cook Strait and Wellington, disrupting sea and air transport on the 24th, following Wellington’s wettest Labour weekend in more than a decade. Rainfall was heavy in parts of Wellington, and a house in Eastbourne was evacuated due to a large landslide.
  • Wellington and Auckland were the wettest, Dunedin the driest, Wellington the coolest, and Christchurch the sunniest of the five main centres. Temperatures were above normal in Dunedin, near normal in Auckland, and Christchurch, and below normal in the two other main centres. Rainfall was above normal in Auckland, Hamilton, Wellington, and Christchurch, and below normal in Dunedin. Sunshine hours were above normal in Christchurch and Dunedin, and below normal in Auckland, Hamilton, and Wellington.

Rainfall

October rainfall totals were about 200 percent (twice) of normal in Auckland, Wairarapa, Manawatu, and just south of Christchurch. Rainfall was also above normal in Wanganui, Wellington, the Kaikoura Coast, and in north Canterbury. Rainfall was just over 50 percent (half) of normal in East Otago.

Temperature

Mean temperatures were just below average in many regions. However, they were more than 1.0°C below average in parts of King Country, coastal Wairarapa, and Wellington, and at least 0.5°C below average in Taupo and Southern Wairarapa.

Sunshine

Sunshine hours were at least 120 percent of normal in inland South Canterbury, East Otago, and Southland, and at least 110 percent of normal in Gisborne, Hawke’s Bay, and North Canterbury. Sunshine hours were below normal in the west of the North Island from Auckland to Wellington.

Full report

For further information, please contact:

Geoff Baird – Communications Manager Phone +64 4 386 0543 [email protected]

Acknowledgement of NIWA as the source is required.

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