Communities across Victoria, New South Wales and Tasmania are bracing for more wild weather after being lashed by heavy rainfall on Thursday.
Towns in each of the three states have been urged to evacuate.
State emergency services are expecting heavy rainfall and potential flooding to continue in the south-east of Australia over the coming weeks.
Authorities are urging people not to drive through floodwaters, saying it removes SES rescue teams from other situations.
"Driving through floodwaters, we know, is the single biggest killer of flooding in Australia," Victorian SES commander Tim Wiebusch said.
Here's the latest in each state.
Victoria
More than 500 homes have flooded in Victoria, Premier Daniel Andrews said, and residents across Melbourne's inner north-west have been urged to evacuate.
Residents in northern and central Victoria are also on high alert, with six areas told to evacuate on Friday morning.
Locals in Wedderburn, Benalla, Carisbrook, Seymour, Rochester and those near the Maribyrnong river in Melbourne's west, were all directed to leave.
At Maribyrnong, residents left their homes with just a few belongings as floodwaters in the area rose above 3.5 metres on Friday.
Around 50 people sought refuge at a local community centre, and many were rescued by boat.
Daniel Andrews said the Mickleham quarantine centre, Victoria's purpose-built COVID quarantine hub, could be used to house people affected by the floods, with the situation expected to worsen.
He warned Victorians to be prepared for six-to-eight weeks of flooding impacts across different parts of the state.
In Wedderburn, emergency services have advised Skinners Flat reservoir is likely to breach, which will cause around 3 feet of fast moving water to flow from the dam.
There are emergency warnings in place for many other communities, including directions for people to move to higher ground in locations such as Barnadown and Euroa
The Campaspe River continues to rise rapidly and is expected to peak on Friday afternoon.
In Carisbrook, near Bendigo, major flooding is occurring from the Loddon River.
Residents expressed frustration on Wednesday that the town was still without a completed levee nearly 12 years after devastating floods in 2011.
Community relief centres have been set up in Echuca and Seymour in the north, Skipton and Creswick near Ballarat, and Maryborough north-west of Melbourne.
Electricity supplier Powercor said it was looking to bring generators to Castlemaine, north-west of Melbourne, after a substation began flooding, forcing the company to turn off power to 9,800 customers.
"We have taken this step to reduce the safety risk to emergency services and our employees and to minimise long-term damage as much as possible in the circumstances," the company said.
On Thursday Mr Wiebusch said that residents in Shepparton, in the north of the state, should brace for flooding this weekend.
He said authorities expected up to 600 properties to be isolated, and around 50 properties to be inundated.
"Shepparton is likely to see major flooding from Saturday afternoon, similar to levels we haven't seen since October 1993," he said.
He said the SES was also expecting major floods from Mount Emu Creek at Skipton, in Victoria's western district, on Saturday.
Within the Skipton community, he said, the SES expected 12 properties and the local shopping strip to be affected, as well as access to the highway to be cut.
On Thursday, major flood warnings were issued for the Campaspe, Goulburn, Loddon, Maribyrnong, Avoca, Werribee, Mount Emu Creek, Ovens and King Rivers as well as Seven and Castle creeks.
Andrew Crisp — the emergency management commissioner with Emergency Management Victoria — said the state should prepare for further flooding.
"Let's learn from this and, if you're not as prepared as you think you should be, then look at how you might do that for future events, as we could be confronted with these events," he said.
He also warned the Eildon, Dartmouth and Thomson dams could spill in coming days.
You can find the latest warnings for Victoria here.
Tasmania
Several people were evacuated and the Bureau of Meteorology warned flooding could continue for days as Tasmania's north was hit with a deluge.
Major warnings were issued for the Mersey and Meander rivers in the state's north, and evacuation centres have been set up in Railton, Latrobe, Ulverstone and Deloraine.
A new alert was issued on Friday morning that the Meander River at the Deloraine Railway Bridge is experiencing "record major flooding".
The river level there is currently at 4.31 metres, and is predicted to reach about 4.5 metres later this morning, above record flood levels.
Evacuation orders were issued between Liena and Latrobe and between Meander and Hadspen.
People were also urged to evacuate from the area of Lake Isandula Dam, which is at risk of failure in the areas of Isandula Road, Preston Road and Gawler Road towards Ulverstone.
And in the early hours of Friday morning an evacuate now order was issued for residents in parts of Newstead, near Hart Street.
BOM senior forecaster Paul Fox-Hughes said yingina/Great Lake had received the highest amount of rain, with 220 millimetres recorded over Wednesday and Thursday.
He said a number of places had recorded 24-hour rainfall records for October.
SES acting director Leon Smith said authorities were in a "very good position from an intelligence position".
"Understanding the rainfall. Understanding where it's actually landing within the catchments, how the catchments are reacting … we're in a really good position given the recent launch of the flood-warning system.
"This is a significant event for Tasmania and we're continuing to treat it very seriously."
You can find the latest warnings for Tasmania here.
New South Wales
In New South Wales, an evacuation order was issued on Thursday for the central west town of Forbes.
The order was expected to affect around 500 residents, who were urged to leave on Thursday night.
The Lachlan River is expected to reach a major flood peak of 10.6 metres on Friday.
An evacuation centre was set up at the Saint Andrew's Presbyterian Church on Harold Street.
A search was continuing in the area for a 63-year-old man thought to have been swept into floodwaters.
He was last seen on a rural properly at Hillston on Tuesday, about 300 kilometres north-west of Wagga Wagga.
You can find the latest warnings for New South Wales here.
