December's climate

New Zealand climate in December 2005

Rainfall (click to enlarge).

Temperature (click to enlarge).

Above average December rainfall was recorded in many regions, particularly in the western North Island and southern South Island. Gisborne, Hawke’s Bay, Central Otago, and Marlborough had below average rainfall.

Mean temperatures everywhere were at least 1.5 °C above average, and more than 3.0 °C above average in parts of Otago and Southland.

For more information on the climate in December, visit the climate summaries page at www.niwa.co.nz/ncc/cs/mclimsum_05_12

Significant soil moisture deficits

Soil moisture (click to enlarge).

By the end of December, significant soil moisture deficits had developed in eastern regions from Hawke’s Bay to Otago, and also in Kapiti, Wellington, and Nelson. These deficits were severe in parts of Marlborough and Central Otago.

 

North Island river flows increase

River flows (click to enlarge).

In December, North Island flows were average or high, apart from the Wellington region where they remained low. Stream flows were higher than normal in Southland and South Otago, but very low elsewhere in the South Island.

October 2005 to December 2005: the climate we predicted and what happened

(click to enlarge).

Rainfall

Rainfall was as predicted in most regions but was drier than expected in the north and west of the South Island and the southwest of the North Island.


(click to enlarge).

Air temperature

The north and east of the North Island were cooler than expected. Other regions were above average as predicted.


(click to enlarge).

River flows

North Island stream flows were normal or high. South Island flows were low or very low, apart from average flows in Southland/Otago, after December rain.


The three outcome maps give the tercile rankings of the rainfall totals, mean air temperatures, and mean river flows that eventuated from October to December, 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.