Sun
Mon
Tue
Wed
Thu
Fri
Sat
14
15
16
17
18
19
20
21
med
22
med
23
med
24
low
25
med
26
27
28
med
29
med
30
low
31
Jan 1
low
2
low
3
low
4
med
5
low
6
low
7
low
8
low
9
10
Chance of rainfall within district |
nil < 25% |
low 25% to 50% |
med 50% to 75% |
high ≥ 75% |
Issue Notes
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, New Zealand, 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 25 December to 29 December, 8 January to 12 January, and 15 January to 19 January. Rain events originating in the tropics and moving south are possible about 10 December to 14 December.
Over Western Australia the strongest cold fronts should occur about 26 December to 30 December, 8 January to 12 January, and 15 January to 19 January.
Issued Dec 12
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.