Weather

Lower Western 28-day rainfall forecast

Sun Mon Tue Wed Thu Fri Sat
        30
 
 
31
 
 
1
Low
Feb
2
Med
 
3
 
 
4
 
 
5
 
 
6
 
 
7
Low
 
8
Low
 
9
Low
 
10
Low
 
11
 
 
12
 
 
13
 
 
14
 
 
15
 
 
16
 
 
17
 
 
18
 
 
19
 
 
20
 
 
21
Low
 
22
Low
 
23
Low
 
24
 
 
25
 
 
26
Low
 
     

Chance of rainfall somewhere within district

Nil
<25%
Low
25-50%
Medium
50-75%
High
≥75%

Issue Notes

Issued 29 Jan 2020

The hemispheric long wave pattern has remained stable in recent weeks. There are seven main troughs. Currently the most significant troughs are near the longitudes of South Africa, the Indian Ocean, Western Australia, eastern Australia, the southeast Pacific, and South America. Summary: Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 7 February to 11 February, 19 February to 23 February, and 2 March to 6 March. Rain events originating in the tropics and moving south are possible about 7 February to 11 February, 25 February to 29 February, and 29 February to 4 March. Over Western Australia the strongest cold fronts should occur about 5 February to 9 February, and 14 February to 18 February.

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.