Three-month outlook

The outlook for September 2005 to November 2005

Local atmospheric circulation patterns are expected to result in more anticyclonic conditions than usual to the east of the South Island, and weaker westerly wind flows, over New Zealand.

Sea surface temperatures around New Zealand are likely to be near or above average until November 2005.

Air temperatures (see maps below) are expected to be above average in the North Island, and average or above average in the South Island.

Rainfalls are likely to be normal or above normal in the east of the North Island and north of the South Island, and near normal elsewhere. Below normal soil moisture levels and river flows are expected on the east coast of the South Island. Elsewhere, normal soil moisture levels and stream flows are expected.

 

A. Climate models give no strong signals about how the climate will evolve, so we assume that there is an equal chance (33%) of the climate occurring in the range of the upper, middle or lower third (tercile) of all previously observed conditions.

B. There is a relatively strong indication by the models (60% chance of occurrence) that conditions will be below average, but, given the variable nature of climate, the chance of average or above-average conditions is also shown (30% and 10% respectively).