Damage assessment crews are swooping in to the remote Western Australian desert town of Fitzroy Crossing as catastrophic floodwaters subside.
Authorities have evacuated or relocated 233 people from the area and responded to 54 calls for help.
In some places the flooded Fitzroy River that runs across the Kimberley north is 50 kilometres wide.
Fire and Emergency Services Commissioner Darren Klemm said he hadn't seen anything like it.
"Any photo you see won't do the scale of it justice," he told reporters on Sunday.
Fitzroy Crossing and the tiny Indigenous community of Noonkanbah were devastated after the river last week reached a record peak of 15.81 metres
Emergency Services Minister Stephen Dawson compared Fitzroy Crossing's airport to Heathrow as flights carried in precious supplies.
The runway had only just reopened on Saturday after flooding closed it, allowing authorities to fly in some 3000 kilograms of food and supplies.
"For everyone across Western Australia at this time, please take care of your family members," Mr Dawson said.
The Australian Defence Force is also working to support towns across the region where record-breaking flooding continues.
Floodwaters are expected to peak in Willare and Pandanus Park in the next 24 hours as the waters head west but rainwater is easing across the catchment.
To the east, people in the Tanami Desert and Sturt Creek District catchments, including those in the Kiwirrkurra community, are being warned to prepare for possible minor flooding expected until Sunday.
Meanwhile, concerns over flooding have eased in the Top End with the intensity of former tropical cyclone Ellie at last subsiding over the southwestern Northern Territory.
A series of earlier severe weather warnings for remote communities in the Simpson, Lasseter and Tanami districts were cancelled by authorities on Sunday morning.
The region had been bracing for impact as Ellie moved back into the NT after wreaking havoc in Western Australia.
"Ex-tropical cyclone Ellie has finally weakened over southwestern parts of the NT," the Bureau of Meteorology said.
"Severe weather is no longer occurring in Northern Territory. Thunderstorm activity in the Simpson district later today may bring isolated heavy rainfall and a severe thunderstorm warning will be issued if this occurs."
While the immediate threat has passed, the situation will continue to be monitored.
Authorities in Queensland say severe thunderstorms and heavy rain are possible on Sunday for the state's north and west.
The communities of Palmerville, Georgetown, Mount Isa, Cloncurry, Urandangi and Boulia are all in the firing line.
Residents in NSW's far west are also being warned that the Darling River is yet to peak.
The town of Menindee has already been inundated but the river could rise to more than 10.7 metres in the coming days, which is higher than the 1976 record.