Climate summary for August 2016

A chilly month for the South Island, rounds of flooding in the North Island.

Temperature

August temperatures were below average (-1.20°C to -0.51°C) in the north and east of the South Island. It was an especially chilly month across the northwestern Tasman region where mean temperatures were well below average (<-1.20°C). Elsewhere in New Zealand, temperatures were near average (-0.50 to 0.49°C).

Rainfall

 

Rainfall was below normal (50-79%) or well below normal (<50%) across Westland, Southland, and parts of the Queenstown-Lakes region. Rainfall was below normal across middle and northern Canterbury, the Tasman, Nelson, and Marlborough regions as well as in parts of Taranaki, Wairarapa, and much of the Bay of Plenty and Waikato. Conversely, rainfall was above normal (120-149%) or well above normal (>149%) for coastal southern Canterbury and coastal Otago and much of Hawke’s Bay as well as north Auckland.

Sunshine

August sunshine was above normal (110-125% of normal) across much of the South Island and west of the North Island. It was especially sunny in southwestern Waikato and in coastal Otago. Sunshine was near normal (90-109% of normal) in most other areas.

Soil Moisture

At the end of August 2016, soil moisture levels were below normal for the time of year across middle and northern Canterbury as well as coastal Wairarapa. Soil moisture levels for the remainder of the country were near normal for this time of year.

Video summary

NIWA Climate Scientist Nava Fedaeff explains the highlights and main centre climate statistics from Winter 2016.

Overview

During August 2016, mean sea-level pressures were lower than normal to the northeast of New Zealand and above normal to the southeast of New Zealand. This pressure pattern resulted in a prevalence of winds from an easterly or southeasterly direction.

August temperatures were below average (-1.20°C to -0.51°C below the August average) across much of the South Island except for the southwestern part of the Island and the Christchurch district, where near average temperatures (-0.50 to +0.49°C) occurred. This was the first month in 2016 that an area this large (on either Island) experienced below average temperatures. It was an especially chilly month in the northwestern Tasman region where well below average temperatures (<-1.20°C below the August average) were recorded. Across the North Island, temperatures were mostly near average. A small area including Wellington and Wairarapa had below average temperatures as well as parts of western Auckland.

The nationwide average temperature in August 2016 was 8.3°C (0.5°C below the 1981-2010 August average from NIWA’s seven station temperature series which begins in 1909). This is the coldest August since 2011, which was -0.8°C colder than average. Despite a cooler than average August, January-August 2016 is the warmest January-August period in the seven station temperature record with departure from average of +1.1°C.

The prevalence of winds from an easterly or southeasterly direction contributed to drier than usual conditions across the west of the South Island with well below normal rainfall (<50% of the August normal) observed in parts of the West Coast, interior Canterbury, interior Otago, and in Southland. In fact, Queenstown had merely 11% of its normal August rainfall and its driest month in over 7 years (since June 2009). A small area of well below normal rainfall was also observed in Taranaki. Below normal rainfall (50-79% of the August normal) was observed across a part of middle and northern Canterbury and much of Tasman, Nelson, and western Marlborough. Much of Waikato, Bay of Plenty, and northern Gisborne, and coastal Wairarapa also had below normal rainfall during August. In contrast, rainfall was well above normal (>149% of the August normal) in some parts of the eastern North and South Islands. Parts of Hawke’s Bay, including Napier, had more than double their normal August rainfall (>200% of normal). Coastal East and North Otago, including Oamaru, also recorded double its normal August rainfall. In addition, the north of the Auckland region had above (120-149% of the August normal) or well above normal rainfall. Rainfall was near normal (80-119% of the August normal) for most of Northland, Manawatu-Whanganui, and Wellington regions.

As of 1 September 2016, soil moisture levels were below normal for the time of year across middle and northern Canterbury as well coastal Wairarapa. Soil moisture levels for the remainder of the country were near normal for the time of year.

August sunshine was above normal (110-125% of normal) across much of the South Island and west of the North Island. It was especially sunny in southwestern Waikato and in coastal Otago. Sunshine was near normal (90-109% of normal) in most other areas.

Further highlights:

  • The highest temperature was 22.2°C, observed at Christchurch (Riccarton) on 29 August.
  • The lowest temperature was -14.1°C, observed at Mt Cook Airport on 8 August.
  • The highest 1-day rainfall was 145 mm, recorded at Tutira (Hawke’s Bay) on 6 August.
  • The highest wind gust was 146 km/hr, observed at Cape Turnagain on 21 August.
  • Of the six main centres in August 2016, Christchurch was the coolest, driest and sunniest, Auckland was the warmest, Wellington was the wettest, and Tauranga was the cloudiest.
  • Of the available, regularly reporting sunshine observation sites, the sunniest four locations in 2016 so far (1 January – 31 August) were Richmond (1855 hours), Blenheim (1708 hours), New Plymouth (1646 hours) and Takaka (1632 hours).

Download 

Download the August 2016 Monthly Climate Summary [PDF 656 KB]

Climate Statistics for August 2016 [70 KB]

Contact

For further information, please contact:

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