Global setting & climate outlook

Global setting

Weak La Niña

Difference from average global SST (click to enlarge).

Monthly SOI values (click to enlarge).

The tropical Pacific is in a weak La Niña state, but should ease to neutral conditions by winter 2006.

Sea surface temperatures (SST) around New Zealand

New Zealand SST (click to enlarge).

SST anomalies in the New Zealand region decreased markedly in March to +0.1 °C (from about +1.0 °C in February). The lower temperatures were associated with cool south to southwest air flows over the country. SST are expected to be near or above average until June.

Outlook for April 2006 to June 2006

Regional outlook (click to enlarge).

During the next three months atmospheric pressures are expected to be higher than normal to the east of the South Island, favouring a tendency for weaker than normal westerlies over New Zealand. Air temperatures are very likely to be above average in the North Island and are likely to be above average in most of the South Island.

Rainfall is likely to be normal or below normal in much of the South Island, and in the southwest North Island. Normal or above normal rainfall is likely for the northern North Island, with near normal falls likely in the east of the North Island.

Soil moisture levels and stream flows are likely to be normal or above normal in the northern North Island, normal in the southeast of the North Island, and below normal in the southwest.

In the South Island, normal or below normal soil moisture levels and stream flows are likely in the north, with drier than normal conditions elsewhere.