January's climate

New Zealand climate in January 2006

Rainfall (click to enlarge).

Temperature (click to enlarge).

Western South Island temperatures plummeted in January, after one of the warmest Decembers on record. Mean January temperatures were up to 1.5 °C below average in parts of Westland and Fiordland. Temperatures were above average in the east and north of the North Island.

A mixed pattern of rainfall occurred over New Zealand in January, with relatively high totals in parts of Northland, Bay of Plenty, Taupo, Hawke’s Bay, and Southland, and comparatively low totals in Horowhenua.

For more information on the climate in January, visit the climate summaries page at www.niwascience.co.nz/ncc/cs/mclimsum_06_01

Persisting soil moisture deficits

Soil moisture (click to enlarge).

Greater than normal soil moisture deficits developed in northern and eastern regions of both islands until the substantial rainfall of 24-25 January. However, significant soil moisture deficits persisted in Manawatu, Wellington, and Wairarapa, and in parts of Canterbury and Central Otago.

 

High flows in some areas

River flows (click to enlarge).

High January streamflows occurred in the northern and central North Island, in northwest Nelson, Buller, and Southland. Near normal flows occurred in part of Northland, much of the North Island east coast, Nelson, inland Marlborough, Canterbury, Otago, and Westland. Low flows occurred in Taranaki, Kapiti Coast, coastal Marlborough, parts of Canterbury, and the Otago high country.

November 2005 to January 2006: the climate we predicted and what happened

(click to enlarge).

Rainfall

Rainfall was higher than predicted in parts of Waikato and the south of the South Island, and lower than predicted in northern and central parts of the South Island.


(click to enlarge).

Air temperature

Air temperatures were above average or average in most areas as predicted, but higher than expected in the east of the South Island.


(click to enlarge).

River flows

Streamflows were normal or above in much of the North Island, coastal Otago, and Southland, and below normal in Taranaki, Wairarapa, Kapiti Coast, and much of the rest of the South Island.


The three outcome maps give the tercile rankings of the rainfall totals, mean air temperatures, and mean river flows that eventuated from November to January, in comparison with the forecast conditions.

As an approximate guide, middle tercile rainfalls typically range from 80 to 115% of the historical normal, and middle tercile temperatures range about the average by plus or minus 0.5 °C.