A thick northwest cloudband could cause rain over a large area of Australia next week as a stream of tropical moisture extends thousands of kilometres from the Indian Ocean towards southeastern Australia.

A slow-moving upper-level trough will cause rain to spread across parts of central Australia this weekend into early next week. This system will then be followed by another upper-level trough next week, which forecast models suggest could produce a northwest cloudband and widespread rain.

These rain-bearing systems will be fuelled by abnormally warm seas surrounding Australia, which will provide extra moisture in the atmosphere to generate rain.

The map below shows how much rain is expected to fall during the next seven days. According to this model (the ECMWF model), widespread totals of 20–40 mm are likely over central and southeastern Australia, with isolated falls of around 40–60 mm possible through parts of SA, Vic, NSW, the ACT and Tas.

Image: ECMWF 7-day rainfall leading up to Thursday, August 20. Source: Weatherzone.

At this stage, further rain could extend into the latter half of next week, possibly allowing parts of southeastern Australia to see accumulated totals of 60–80 mm between now and Sunday, August 23.

There is some uncertainty regarding where and how much rain will fall next week. Be sure to stay up to date with the latest forecasts and warnings for the most accurate information.