Three-month outlook

The outlook for August 2005 to October 2005

Local atmospheric circulation patterns are likely to lead to more westerly air flows than usual to the south of New Zealand, and anticyclonic conditions east of the South Island.

Air temperatures are expected to be above average in many regions, but near or above average in the east of the North Island and the north of the South Island.

Rainfalls are likely to be normal or above normal in eastern districts of both islands, and near normal elsewhere.

Soil moisture levels are expected to be normal everywhere except for the North Island east coast, where normal or above normal levels are expected. River flows are expected to be normal everywhere.

 

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).