Spring 2008

Dry in the north and east, mild and sunny for much of the country.

Dry in the north and east, mild and sunny for much of the country. Westerly gales at times.

  • Rainfall: Below normal for north and east of North Island and east of South Island, with significant soil moisture deficits in eastern areas
  • Temperature: Above average in Canterbury and Central Otago, below average on the West Coast and Tararua district
  • Sunshine: Above normal for parts of Northland, central and eastern North Island, Mount Cook and coastal Otago

Spring rainfall was below normal in the east with less than 50 percent (half) of normal in parts of Gisborne, Hawkes Bay, and south Canterbury, and between 50 and 80 percent of normal in parts of Northland, Auckland, Bay of Plenty, Marlborough, Canterbury and Otago. As a result significant soil moisture deficits had developed throughout eastern areas from Gisborne to Otago by the end of spring. Other areas received near normal rainfall for spring.

Spring overall was warmer than average in parts of Canterbury and Central Otago, and below average on the West Coast and parts of the Tararua district. The national average temperature of 12.4 °C was 0.3 °C above average for spring.

The overall spring climate pattern was dominated by more anticyclones (‘highs’) located to the east of New Zealand extending ridges over northern New Zealand. There were stronger than normal northwesterly winds over the South Island, which contributed to the soil moisture deficits in the east, low rainfalls in the north and east, and damaging westerly wind events in the east of the South Island and lower North Island.

Major highlights

  • Heavy rain in Taranaki on 7 October caused flash floods in mountain streams, resulting in the death of a tramper who was swept away attempting to cross the swollen Kaupokonui Stream on Mt Taranaki, hampered by a heavy back-pack. Heavy rain from a northerly subtropical flow caused floods in Nelson and the West Coast on 24 November.
  • The lowest temperature during spring was recorded at Lake Tekapo on the 25th of October, where the minimum temperature was -6.1°C. The maximum temperatures on the 4th, 5th and 6th of September were quite low for many locations, with Hanmer only reaching 2.8°C on the 5th (the lowest maximum for spring).
  • The highest temperature during spring 2008 was 33.3°C recorded at Waione (Wairarapa) on the 24th of November. The minimum temperature of 19.2°C at Wanganui on the night of the 23rd/24th of November was the highest minimum for the country for spring.
  • Seven damaging westerly wind episodes occurred during spring, impacting the east of the South Island and lower North Island. Winds gusts reached 140 km/hr on 23 September at Swampy Summit above Dunedin, 100 km/hr at Taiaroa Head, 135 km/hr on the Rock and Pillar Range, near Middlemarch. Wind speeds of up to 130 kph were recorded in Wellington, and up to 160 kph in some of the surrounding hills on 7 October. Winds of up to 140 km/hour hammered Wellington, lifting roofs, cutting power, and disrupting flights on 1 November.
  • There were two major snowfall events in spring. The first occurred on 27 September bringing snow to low elevations in Otago and Southland. The second, on November 5, blanketed inland Southland, Fiordland and Central Otago with snow and hail. Locals said it was the first time since the 1970s that they have seen this much snow in November.
  • Of the five main centres, Auckland had the warmest average spring temperature, Wellington was the wettest, and Christchurch was the sunniest and driest. Spring temperatures were near or slightly above average and spring rainfall was near or below normal in all five locations. Spring sunshine was above normal in Auckland and Christchurch and well above normal in Dunedin.

Rainfall

Spring rainfall was less than 50 percent (half) of normal in parts of Gisborne, Hawkes Bay, and south Canterbury and between 50 and 80 percent of normal in parts of Northland, Auckland, Bay of Plenty, Marlborough, Canterbury and Otago. Other areas received near normal rainfall for spring.

Temperature

Seasonal mean temperatures were between 0.5 and 1.5 °C above average in parts of Canterbury and Central Otago. They were below average by about 0.5 °C on the West Coast and by about 1.0 °C around Dannevirke. The national average temperature of 12.4 °C was 0.3 °C above average for spring.

Sunshine

Spring sunshine hours were at least 110 percent of normal in parts of Northland, King Country, Hawkes Bay, Taraura district, Mount Cook and coastal Otago. In the Tasman district totals were lower than usual, being 90 percent of normal.

Full report

Acknowledgement of NIWA as the source is required.

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