Autumn 2016

Second warmest autumn on record, wet for the West Coast.

Temperature

Autumn temperatures were well above average (>1.20°C) for New Zealand. Pockets of above average temperatures (+0.51°C to +1.20 °C) were observed in Gisborne, Waikato, Marlborough, Nelson, Tasman, the West Coast and Southland. No locations observed average temperatures (-0.50°C to +0.50°C) or below average temperatures.

Rainfall

 

Rainfall was above normal (120-149%) for the western portion of the South Island. Rainfall in northern and eastern parts of the North Island as well as Marlborough and Canterbury was below normal (50-79%). Near normal rainfall (80-119%) was observed in western Waikato, Taranaki, Manawatu-Whanganui and western Wellington.

Sunshine

Autumn sunshine was near normal for the majority of the country. Above normal sunshine (110-125%) was observed in Northland, parts of Auckland and eastern parts of the Gisborne, Wellington, Canterbury and Otago regions.

Soil Moisture

As at 1 June 2016, soil moisture levels were below normal for the time of year for large parts of Gisborne, Hawke’s Bay, and the Wairarapa as well as central and northern parts of Canterbury. Soil moisture levels for the remainder of the country were near normal for the time of year.

Overview

During autumn, air pressure was lower than normal south of Australia while slightly higher than normal pressures existed to the northeast of New Zealand. The resulting pressure gradient led to a prevalence of north-westerly wind flow throughout the season. In addition to frequent north-westerlies, warmer than usual sea surface temperatures, particularly to the west of the country persisted throughout autumn. The combination of these two factors contributed to the exceptional warmth felt across New Zealand throughout all three months of autumn.  Virtually every climate station in New Zealand recorded above average (+0.51°C to +1.20 °C) temperatures or higher during autumn, with numerous locations experiencing record or near-record warmth (particularly in the North Island). The nationwide average temperature in autumn 2016 was 14.7°C [1](1.4°C above the 1981-2010 autumn average from NIWA’s seven station temperature series which began in 1909), making autumn 2016 the 2nd warmest autumn on record using this series.  The warmest autumn on record was autumn 1938.

Rainfall

Rainfall throughout the months of autumn was variable. It was particularly wet in Tasman, West Coast and western Southland during May (in excess of 200% of normal May rainfall was recorded there) and as a result rainfall for the season as a whole was above (120-149%) to well above (>149%) normal. Conversely, rainfall in northern and eastern parts of the North Island as well as Marlborough and Canterbury was below normal (50-79%). Pockets of well below normal rainfall (<50%) were recorded in Northland, Gisborne, Hawke’s Bay, eastern Wellington and Canterbury.

Soil moisture

Soil moisture levels at the beginning of autumn were below normal for the time of year for the lower North Island and Canterbury. April was a particularly dry month in the North Island and eastern South Island. As a result, soil moisture levels in these regions gradually decreased as autumn progressed. The arrival of steady rain during the second half of May led to soil moisture levels gradually rising to near normal in southern Canterbury, Otago, Southland, the West Coast and western parts of the North Island. As at 1 June 2016, soil moisture levels remain below normal for the time of year for large parts of Gisborne, Hawke’s Bay, the Wairarapa as well as central and northern parts of Canterbury.

Sunshine

Autumn sunshine was near normal for the majority of the country. Above normal sunshine (110-125%) was observed in Northland, parts of Auckland and eastern parts of Gisborne, Wellington, Canterbury and Otago.

Further Highlights:

  • The highest temperature was 33.1°C, observed at Hastings, Napier and Gisborne on 8 March
  • The lowest temperature was -5.6°C, observed at Ranfurly on 25 May.
  • The highest 1-day rainfall was 304 mm, recorded at Takaka on 23 March.
  • The highest wind gust was 196 km/hr, observed at Cape Turnagain on 10 March.
  • Of the six main centres in autumn 2016, Auckland was the warmest and sunniest, Dunedin was the coldest, Christchurch was the driest, Tauranga was the wettest and cloudiest
  • Of the available, regularly reporting sunshine observation sites, the sunniest four locations in 2016 so far (1 January – 31 May) were Richmond (1289 hours), Blenheim (1167 hours), New Plymouth (1164 hours) and Takaka (1123 hours).

Download 

Download the full Autumn Seasonal Climate Summary for 2016 [717KB PDF]

Contact

For further information, please contact:

Mr Chris Brandolino
Principal Scientist – Forecasting, NIWA National Climate Centre
Tel. 09 375 6335, Mobile 027 886 0014

 



[1] Interim value