28 Day Rainfall Forecast
Great Southern Rain Forecast
Great Southern 28-day Rainfall Forecast
Sun Mon Tue Wed Thu Fri Sat1415Hig16Hig17Hig181920Low2122232425262728293031Sep 1234567891011CHANCE OF RAINFALL WITHIN DISTRICTNil< 25%Low25 - 50%Medium50 - 75%High≥ 75%
Issue NotesIssued 14 Aug 2022
The hemispheric long wave pattern has been relatively fast moving in recent weeks. There are four main troughs. Currently the most significant troughs are near the longitudes of the southwest Indian Ocean, Western Australia, eastern Australia, New Zealand, and the southeast Pacific.
Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 12 August to 16 August. Rain events originating in the tropics and moving south are possible about 12 August to 16 August. Over Western Australia the strongest cold fronts should occur about 12 August to 16 August.Forecast Explanation
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.