Sun
Mon
Tue
Wed
Thu
Fri
Sat
11
low
12
13
14
15
16
17
18
19
20
21
22
low
23
med
24
med
25
low
26
27
28
low
29
30
low
31
low
Jan 1
2
low
3
4
low
5
6
7
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, the Indian Ocean, eastern Australia, New Zealand, the south Pacific, and the Atlantic Ocean.
Summary:
Over southern and eastern Australia the cold front events with potential to bring widespread rain are now expected about 16 December to 20 December, 20 December to 24 December, and 27 December to 31 December. Rain events originating in the tropics and moving south are possible about 27 December to 31 December, 31 December to 4 January, and 9 January to 13 January.
Over Western Australia the strongest cold fronts should occur about 18 December to 22 December, 6 January to 10 January, and 12 January to 16 January.
Issued Dec 9
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.