Weather

Lower West 28-day rainfall forecast

Sun Mon Tue Wed Thu Fri Sat
19
 
 
20
 
 
21
Low
 
22
 
 
23
 
 
24
 
 
25
 
 
26
 
 
27
 
 
28
Low
 
29
Low
 
30
Low
 
31
Low
 
1
Low
Feb
2
Low
 
3
Low
 
4
 
 
5
 
 
6
 
 
7
Low
 
8
 
 
9
Low
 
10
 
 
11
Low
 
12
Low
 
13
 
 
14
 
 
15
 
 

Chance of rainfall somewhere within district

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

Issue Notes

Issued 17 Jan 2020

The hemispheric long wave pattern has been relatively fast moving in recent weeks. There are three main troughs. Currently the most significant troughs are near the longitudes of South Africa, Western Australia, and the south Pacific. Summary: Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 22 January to 26 January, 31 January to 4 February, and 5 February to 9 February. Rain events originating in the tropics and moving south are possible about 8 February to 12 February. Over Western Australia the strongest cold fronts should occur about 22 January to 26 January, 31 January to 4 February, and 5 February to 9 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.