Perth 28-day Rainfall Forecast
|Chance of rainfall within district|
25% to 50%
50% to 75%
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, Western Australia, eastern Australia, the south Pacific, and South America.
Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 9 April to 13 April, 14 April to 18 April, and 1 May to 5 May. Rain events originating in the tropics and moving south are possible about 24 April to 28 April.
Over Western Australia the strongest cold fronts should occur about 13 April to 17 April, 21 April to 25 April, and 29 April to 3 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.
Cyclone Debbie: Northern NSW residents urged to evacuate as south-east QLD braces for more severe weather
Northern NSW residents have been ordered to evacuate ahead of "unprecedented" flooding in the region, and south-east Queensland is hit by severe weather expected to worsen overnight, as ex-Tropical Cyclone Debbie continues along the east coast.
Ex-Tropical Cyclone Debbie's reign is not yet over, authorities say, with warnings severe weather may worsen for south-east Queensland overnight.
Residents in the Whitsundays in central Queensland have been urged not to drink tap water for the next few days due to health risks.