Science Centres: Climate

During July-September, mean sea level pressures are likely to be above normal over the North Island and to the north of the country, with a westerly flow anomaly over the South Island and south of the country. Temperatures are likely to be above average in most regions. Rainfall is likely to be normal or below normal over the North Island and normal or above normal over the South Island.

For the rest of the winter and into early spring, temperatures are likely to be above average in the North Island and northern South Island, and average or above average elsewhere. Nevertheless, cold spells and seasonal frosts are still expected, especially in the South Island and central North Island. 

Rainfall is likely to be normal or below normal over the North Island, normal or above normal over the western South Island, and near normal elsewhere.

Soil moisture levels and stream flows are likely to be normal or below normal in the north and east of the North Island, normal or above normal in the western South Island, and near normal in other regions.

In this example below, the climate models suggest that below normal conditions are likely (50% chance), but, given the variable nature of the climate, the chance of normal or above normal conditions is also shown
(30% and 20% respectively).

See our full July-September 2010 climate outlook