March's climate

New Zealand climate in March 2006

Rainfall (click to enlarge).

Temperature (click to enlarge).

March was cold, with mean temperatures being the lowest since 1993. The national average temperature of 14.2 °C (almost 3.0 °C lower than in February) was 1.5 °C below the 1971-2000 normal.

Rainfall was above average in many northern and eastern parts of the North Island and in coastal Southland. Some high falls in Northland were associated with the passage of ex-tropical cyclone Wati. Elsewhere, rainfall was below normal in Nelson, inland south Canterbury, and many western regions.

For more information on the climate in March, visit the climate summaries page at www.niwascience.co.nz/ncc/cs/mclimsum_06_03

Soil moisture: persisting deficits

Soil moisture (click to enlarge).

Significant soil moisture deficits persisted during the first three weeks of March in Northland, Auckland, and Gisborne, and continued for the rest of the month in Wanganui, Manawatu, Nelson, and the east of the South Island from Canterbury to Central Otago.

 

Isolated high flows; otherwise low

River flows (click to enlarge).

Above normal stream flows occurred in coastal Southland, and in the northern North Island regions that were affected by ex-tropical cyclone Wati. Low flows occurred in the southwest of the North Island and in the northern and central South Island. Stream flows were extremely low in Nelson and in central South Island catchments.

January 2006 to March 2006: the climate we predicted and what happened

(click to enlarge).

Rainfall

Rainfall was as predicted in many districts, but drier than predicted in western parts of the southern North Island and north and northwest of the South Island.


(click to enlarge).

Air temperature

Air temperatures were as expected in the eastern North Island, but below predictions elsewhere.


(click to enlarge).

River flows

Normal stream flows in much of the North Island and coastal Southland; below normal in Taranaki, Kapiti Coast, Nelson, and the central South Island.


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