Current Climate - October 2009

During October 2009, lower than normal pressures and frequent southeasterly winds affected New Zealand, leading to the low temperatures around the country. Southeasterlies also led to the sunny and dry conditions experienced on the west coast of the South Island, as the Southern Alps provided shelter from the wind.

Percentage of normal rainfall, October 09.

End of month water balance in the pasture root zone for an average soil type, where the available water capacity is 150 mm.

Departure from average air temperature for October 2009.

Rainfall

Well above normal October rainfall (above 150 percent of normal) was experienced across the East Coast of the North Island, as well as Wellington, Marlborough and Canterbury (north of about Ashburton).  Rainfall was near-record (and more than 200 percent of normal) in parts of Hawkes Bay, Gisborne and the Tararua District.  Rainfall was also above normal (between 120 and 150 percent of normal) in Manawatu-Wanganui, Waikato and the Bay of Plenty.  Rainfall totals were near normal (between 80 and 120 percent of normal) in the Tasman District, central Otago, Auckland, Taranaki and western parts of Northland. In contrast, it was very dry on the West Coast and in Fiordland, with only about half of normal October rainfall recorded there. 

Air temperature

Record or near-record low October temperatures were experienced in many locations, with temperatures more than 2.0°C below average throughout eastern and alpine areas of the South Island, as well as in the lower half of the North Island. Temperatures were below average (between 0.5°C and 1.2°C below average) elsewhere.  Overall for New Zealand, it was the coldest October in 64 years (since 1945), with a national average temperature of 10.6°C (1.4°C below the long-term October average).  Such a cold October has occurred only four times in the past 100 years.  Record low October temperatures were recorded on the 4th/5th in most North Island locations, and on the 9th at many South Island sites.

Sunshine

October sunshine totals were well above normal (more than 125 percent of normal) on the West Coast and in Fiordland; in contrast, sunshine totals were below normal (between 75 and 90 percent of normal) for Taranaki, Wellington and the Wairarapa. Elsewhere, sunshine totals were in the near normal range.

See our October 2009 climate summary.

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