|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, eastern Australia, New Zealand, the south Pacific, and the Atlantic Ocean.
Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 1 May to 5 May, 5 May to 9 May, and 10 May to 14 May. Rain events originating in the tropics and moving south are possible about 23 April to 27 April.
Over Western Australia the strongest cold fronts should occur about 30 April to 4 May, 4 May to 8 May, and 10 May to 14 May.
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.
15:06 AEST Night-time temperatures will drop well below average in the Capital from Wednesday.