Current Climate - November 2014

November 2014 was characterised by air pressures which were lower than normal over New Zealand and to the south of the Chatham Islands, with higher pressures than normal present in the north Tasman Sea. 

This pressure pattern resulted in westerly flow anomalies over New Zealand.  Southerly outbreaks occurred frequently during the month, and these contributed to the changeable and generally unsettled weather that characterised the month for many parts of the country.

Rainfall

The westerly flow anomaly for the month as a whole contributed to rainfall totals that were above normal (120-149%) or well above normal (> 149%) for western and southern parts of the South Island, and isolated locations in the North Island including Palmerston North, Whanganui and Dargaville.  The orographic effect of air moving eastwards over elevated land meant that rainfall was below normal (50-79%) or well below normal (< 50%) in eastern parts of both islands such as Central Otago, South Canterbury, Marlborough, Hawke’s Bay, Gisborne, Bay of Plenty and the Coromandel Peninsula.  It was a similarly dry month for Nelson, Wellington, the Kapiti Coast and Auckland. Remaining areas of the country typically received near normal rainfall (within 20% of normal) for the month.

Temperature

November temperatures were below average (-1.20°C to -0.51°C) for many parts of the country, particularly for southern and western parts of the South Island, and central, western and northern-most parts of the North Island.  It was a particularly cold month for Fiordland, parts of the Southern Lakes and Central Otago, the Canterbury High Country and central-western parts of Waikato where temperatures were well below average (> 1.20°C below average).  In contrast, isolated locations including Kaikoura and Te Kuiti recorded above average temperatures (+0.51°C to +1.20°C).

Sunshine

Most of the country received near normal (90-109%) or above normal (110-125%) sunshine hours for November.  It was particularly sunny for eastern areas of the North Island, and eastern and northern parts of the South Island, with well above normal sunshine (> 125%) observed in Gisborne, Blenheim and Cheviot. In contrast, it was a cloudy month for south-western parts of the South Island, where sunshine was below normal (75-90%) or well below normal (< 75%) for the south-western parts of the South Island.

Soil Moisture

As of 1 December 2014, soil moisture levels throughout New Zealand were closely reflective of the rainfall anomalies observed during November.  Soils had dried considerably for many areas of the North Island in comparison to the soil moisture levels observed on 1 November.  Specifically, soils had become notably drier than normal for Wellington, southern Wairarapa, Hawke’s Bay, Gisborne and Bay of Plenty.  In the South Island, soils around the Nelson region had become considerably drier than normal for the time of year, whilst soils on the east coast of the South Island remained drier than normal.  In contrast, soils were wetter than normal for the south of the South Island on the back of an especially wet November.  Soil moisture levels were largely near normal for remaining parts of New Zealand.