|Chance of rainfall within district|
25% to 50%
50% to 75%
The hemispheric long wave pattern has remained stable in recent weeks. There are six main troughs. Currently the most significant troughs are near the longitudes of South Africa, the Indian Ocean, New Zealand, the south Pacific, the southeast Pacific, and South America.
Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 1 December to 5 December, 5 December to 9 December, and 11 December to 15 December. Rain events originating in the tropics and moving south are possible about 27 November to 1 December, 7 December to 11 December, and 11 December to 15 December.
Over Western Australia the strongest cold fronts should occur about 1 December to 5 December, 5 December to 9 December, and 10 December to 14 December.
This forecast is produced by a multi-model ensemble consisting of dynamical atmospheric models, which are forced by the latest observed atmosphere, ocean, land and ice conditions. The models are designed to simulate features of the real atmosphere, including the daily movement of long and short wave patterns in the Southern Hemisphere.
The future probability of rain in each district is estimated using output from the multi-model ensemble, combined with historical information about the difference between the model forecasts and observed rainfall.
In this deterministic framework the skill of the forecast tends to decrease with time, however the forecasts are updated daily to provide the latest estimates of rainfall probability out to 28 days.
21:10 EDT Firefighters have put out several grass fires around Sydney and warned that any bushfires that develop will be extremely difficult to control, as temperatures are forecast to remain high over the weekend.