Climate Summary for October 2014

A dry month for some of the country with near average temperatures for most.

Rainfall

 

Rainfall was below normal (50-79%) or well below normal (< 50%) for many eastern and northern areas of the South Island, Wellington, Wairarapa, the Kapiti Coast, Hawke’s Bay, Gisborne and the Bay of Plenty.  Conversely, rainfall was above normal (120-149%) or well above normal (> 149%) for south-western parts of the South Island.

Temperature

October temperatures were near average (within 0.50°C of average) for many parts of New Zealand.  Temperatures were below average (-1.20 to -0.51°C) for isolated inland parts of Southland and Otago, Waitomo and the Far North, and above average (+0.51°C to +1.20°C ) in parts of Bay of Plenty.

Soil Moisture

As of 1 November 2014, soil moisture levels for most eastern and northern parts of the South Island were below normal for the time of year, while levels for the remainder of the South Island were near normal. Soil moisture levels were above normal in the Far North, Auckland, Hawke’s Bay and parts of Manawatu-Whanganui.

Sunshine

A sunny October for the lower half of the North Island as well as northern, central and south-eastern areas of the South Island, with above normal sunshine (110-125%) recorded in many of these areas. Near normal (90-109%) sunshine for most remaining areas of the country.

Overview

October 2014 was characterised by air pressures which were lower than normal over and to the south-east of the country. This resulted in an anomalous south-westerly flow over New Zealand.  This southwest flow anomaly is clearly illustrated by the rainfall anomalies observed across New Zealand for October (see rainfall anomaly map on the last page of this document).  Areas exposed to the south-westerlies received rainfall that was above normal (120-149%) or well above normal (> 149%).  Indeed, such rainfall anomalies were experienced in south-western Southland and Fiordland.  In contrast, areas sheltered from the south-westerlies received below normal (50-79%) or well below normal (< 50%) rainfall, and this was the case for eastern and northern parts of the South Island, as well as the lower North Island, Hawke’s Bay, Gisborne and the Bay of Plenty.  Remaining areas of the country typically received near normal rainfall (within 20% of normal) for the month.

Soil moisture levels on the east coast of the South Island were below normal for the time of year at the start of the month, and this remained the case as of 1 November 2014 after a relatively dry October there.  Likewise, at 1 November 2014 soils were drier than normal for the time of year in Marlborough and Nelson.  Soils were wetter than normal in the Far North, Auckland, and parts of Manawatu-Whanganui.  Soils were also wetter than normal in Hawke’s Bay despite the region receiving below normal rainfall in October: soil moisture levels have remained relatively high as a result of above normal September rainfall that was received in the region.  Soil moisture levels were near normal for the time of year for remaining areas of New Zealand.

October saw near average temperatures (within 0.50°C of average) for most areas of the country overall.  However, there was considerable day-to-day variability of temperatures at times as the anomalous south-westerly flow for the month overall (as outlined earlier) shifted between more westerly and southerly variations.   Temperatures were much cooler than average during the early part of October, with a cool southerly flow bringing snow to low elevations in both the North and South Islands.  The latter half of the month saw warmer than average temperatures across most of New Zealand.  This effectively offset the cold start to the month, meaning temperatures were near average across most of New Zealand for the month as a whole.  However, October was a cool month for isolated inland parts of Southland and Otago, Waitomo and the Far North, where temperatures were below average (-1.20 to -0.51°C), while above average temperatures (+0.51°C to +1.20°C) were observed in isolated inland parts of Bay of Plenty. The nation-wide average temperature in October 2014 was 12.2°C (0.1°C above the 1971-2000 October average from NIWA’s seven station temperature series which begins in 1909)[1].

October was a sunny month for the lower half of the North Island as well as northern, central and south-eastern areas of the South Island, with above normal sunshine (110-125%) recorded in many of these areas. Balclutha, Dunedin, Cheviot and Martinborough enjoyed near-record high sunshine hours for the month.  Sunshine hours were near normal (90-109%) for most remaining areas of the country.

Further Highlights:

  • The highest temperature was 27.5°C, observed at Christchurch (Riccarton) on 17 October.
  • The lowest temperature was -4.9°C, observed at Middlemarch on 25 October.
  • The highest 1-day rainfall was 204 mm, recorded at Milford Sound on 5 October.
  • The highest wind gust was 196 km/hr, observed at Cape Turnagain on 6 October.
    • Of the six main centres in October 2014, Auckland was the warmest, Dunedin was the coolest, Christchurch was the driest, Hamilton was the wettest and cloudiest and Wellington was the sunniest.
    • Of the available, regularly reporting sunshine observation sites, the sunniest four centres[2] so far in 2014 (1 January to 31 October) are: Whakatane (2216 hours), Lake Tekapo (2020 hours), Nelson (2005 hours) and Blenheim (1997 hours).

 

For further information, please contact:

Mr Chris Brandolino
NIWA Forecaster – NIWA National Climate Centre
Tel. 09 375 6335, Mobile (027) 886 0014

Download the full report:

Climate Summary for October 2014 [550.21Kb PDF]

Climate statistics table:

Climate statistics for October 2014 [62Kb PDF]