Australia Weather News

Widespread rain is expected across central Australia over the coming days. - ABC

Its border might still be closed, but Australia's south-east is set to get a taste of Queensland this weekend as a complex low pressure system moseys across the continent bringing tropical moisture, rain and storms.

According to BOM senior meteorologist Dean Narramore, parts of the central and eastern interior could get falls of 20 to 50 millimetres, with isolated thunderstorms that could bring up to 100mm for South Australia, western New South Wales and south-west Queensland.

These are pretty big numbers for parts of the world that do not usually get a lot of rain.

The forecast falls will come from a complex cut-off low pressure system that is expected to form around the WA-SA border tonight and slowly make its way east over the coming days, tapping into tropical moisture from the Coral Sea.

Showers and storms are expected across southern WA this evening, before the widespread rain moves in to SA and southern Victoria tomorrow.

By the end of Thursday, the rain is expected to extend all the way into the southern Northern Territory.

"We could even see a shower or storm up around Alice Springs by then end of the day," Mr Narramore said.

Friday is expected to see more showers and storms for South Australia as well as parts of south-west Queensland.

By Friday evening and into Saturday, the system is expected to move further east, bringing falls to western NSW and northern and western Victoria.

"The band will also slowly move through southern Queensland, but with showers slowly clearing from the NT and western parts of SA," Mr Narramore said.

The system is expected to weaken as it gets to the east coast on Sunday where only light showers are likely.

Muggy few days ahead

It is going to be quite muggy for Melbourne and Sydney ahead of the rain and thunderstorm activity, according to Mr Narramore.

"Much of eastern and south-eastern Australia, particularly Friday and Saturday, are going to see a warm and humid few days."

Parts of northern Victoria and western and southern NSW are expected to see their highest temperatures since last summer and reach the low 30s.

"It will feel like Queensland for much of Victoria and NSW," Mr Narramore said.

Is it a sign of things to come?

The talk of the town in weather circles this season is the impending La Nina.

The latest update from the BOM indicated we are stilljustbelow the official La Nina level, but it is looking increasingly likely that we will officially get there soon.

As Mr Narramore explained, with a La Nina there is typically more moisture available for systems like this one to tap into as they move across the country.

"Systems like this will probably become a bit more common as we move into the coming months, meaning more widespread areas of rain and storms," he said.

"More humidity for the east and south-east is probably something that we're going to have to get used to in the coming months as we move deeper into spring and summer."

Lake Eyre?

Talk of desert rain will always get the romantic among us excited about the prospect of seeing those desolate salt pans, optimistically labelled lakes, fill with water.

But Mr Narramore said the heaviest falls this week were likely to miss but it could still get 10 to 20 millimetres.

"All the rivers that feed into Lake Eyre are looking to get closer to 25mm to 50mm, but because it is so dry it is highly unlikely that any of that water will reach the lake."

Bob Backway, commodore of the Lake Eyre Yacht Club, said while there was often at least one rain event between June and October, rainfall during this time of year had never been enough to fill the lake.

"But it is looking good for this summer," he said.

It is generally the big summer monsoonal rains that send the floods their way and a La Nina will certainly give them reason to be hopeful.

"Lake Eyre Yacht Club members are eternally optimistic," Mr Backway said.

As the system moves through, severe weather warnings are likely to be issued.

Check the warnings with the BOM or your local ABC on Facebook or radio and heed the advice of your emergency services.

ABC