28 Day Rainfall Forecast
Channel Country Rain Forecast
Channel Country 28-day Rainfall Forecast
Sun Mon Tue Wed Thu Fri Sat222324252627282930Oct 1234567891011121314Low151617181920CHANCE OF RAINFALL WITHIN DISTRICTNil< 25%Low25 - 50%Medium50 - 75%High≥ 75%
Issue NotesIssued 22 Sep 2020
The hemispheric long wave pattern has remained stable in recent weeks. There are five main troughs. Currently the most significant troughs are near the longitudes of South Africa, the southwest Indian Ocean, the Indian Ocean, New Zealand, 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 28 September to 2 October, 12 October to 16 October, and 24 October to 28 October. Rain events originating in the tropics and moving south are possible about 18 October to 22 October, and 25 October to 29 October. Over Western Australia the strongest cold fronts should occur about 28 September to 2 October, 19 October to 23 October, and 24 October to 28 October.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.