- Rainfall: Wet in the north and west of the North Island, especially Northland, western Bay of Plenty, and Wanganui; below normal in Hawke’s Bay and Marlborough
- Soil moisture: Significant deficits in eastern regions from Hawke’s Bay to Otago, as well as Kapiti, Wellington and Nelson
- Temperatures: Well above average in most places, third warmest December on record
- Sunshine: Normal or below normal throughout New Zealand
Contrasts in rainfall occurred in December, with extremely high totals in northern parts of Northland, western Bay of Plenty, and Wanganui (highest in 115 years of record), and comparatively low totals in parts of Hawke’s Bay and coastal Marlborough. Significant soil moisture deficits occurred in eastern regions from Hawke’s Bay to Otago, as well as Kapiti, Wellington and Nelson, being severe in parts of Marlborough and Central Otago. Temperatures were remarkably high throughout the nation. The national average temperature was 17.5 °C, 1.9 °C above average. This was the warmest December in 71 years (18.5 °C in 1934), and third warmest since reliable records commenced in the mid 1860s (December 1872 had 17.8 °C). Sunshine hours were normal or below normal throughout New Zealand. December mean sea level pressures were well below average in the Australian Bight, extending troughs of low pressure ('lows') toward New Zealand. This pattern produced more frequent warm northerlies over the North Island and more northeasterly airflow than average over the South Island.
Other Highlights
- The highest temperatures during December 2005 were 31.7 °C recorded at Darfield on the 30th, and 31.5 °C at Napier Airport on the 31st. The lowest temperature for the month was 1.5 °C at Chateau Ruapehu on the 25th.
- Periods of high rainfall affected parts of the North Island from Northland to Wanganui between the 13th and 17th.
- The highest wind gust for the month was 137 km/h from the northwest, at Castlepoint on the 4th.
- Damaging hailstorms occurred in Southland on both the 5th and 15th.
- Damaging tornadoes, or tornado-like winds occurred in Rotorua on the 6th, and Southland on the 15th.
- Lightning strikes left many people temporarily without power in Taranaki on the 6th.
- Of the four main centres Christchurch was the driest, and Dunedin wettest. Rainfall was above average in Dunedin, near average in Auckland and Wellington, and below average in Christchurch. Temperatures were above average in all four main centres. Sunshine hours were near average in Auckland and Wellington, and below average in Christchurch and Dunedin.
Rainfall
Rainfall was at least 300 percent (triple) of normal in northern parts of Northland, and at least 200 percent (twice) of normal in western Bay of Plenty, and Wanganui. It was also wetter than average in Thames, inland Bay of Plenty, Waikato, King Country, southern Taranaki, Manawatu, coastal parts of south Canterbury, and western and inland Southland. Rainfall was less than 50 percent of normal in parts of Hawke’s Bay, and also below normal in Marlborough.
Temperature
Mean temperatures were at least 1.5 °C above average throughout much of New Zealand. They were 3.0 °C or more above average in parts of Otago, and Southland, and at least 2.0 °C above average in eastern Bay of Plenty, the west of the North Island from Manawatu to Wellington, and most of the South Island.
Sunshine
Sunshine hours were 80 percent or less of normal in Waikato, King Country, Nelson, and coastal north Canterbury, and less than 90 percent of normal in Taranaki, inland Canterbury, and Otago. They were near normal elsewhere.
Full report
- Full details of the December 2005 Climate Summary
For further information, please contact:
Dr Jim Salinger – Principal Scientist, Climate NIWA National Climate Centre – Auckland Phone +64 9 375 2053 [email protected]
Stuart Burgess – Climatologist NIWA National Climate Centre – Wellington Phone +64 4 386 0569 [email protected]
Geoff Baird – Communications Manager Phone +64 4 386 0543 [email protected]
Acknowledgement of NIWA as the source is required.