Australia should prepare for a treacherous wet season, Prime Minister Anthony Albanese says, while visiting the flooded NSW town of Forbes.
Thousands of people in the central western town have been impacted after the Lachlan River burst its banks, inundating the city centre and forcing evacuations last week.
The latest flood is Forbes' fifth in 12 years.
Mr Albanese on Monday visited Forbes with NSW Premier Dominic Perrottet, as major warnings remain in place for eight rivers across the state.
A number of inland rivers and creeks were also placed on flood watch on Monday, with major flooding possible later in the week.
"We are living in very dangerous times in the days and weeks ahead," Mr Albanese said.
Relentless rain in western NSW, Victoria and Tasmania is likely to continue to cause flooding in the coming weeks, he said.
The prime minister urged people to follow warnings, with too many dismissing advice to evacuate.
"(People are) saying 'no, we'll be right'," Mr Albanese said.
That attitude led to multiple rescues in flooded regions, putting emergency personnel at risk, he said.
Mr Perrottet said the floods that have hit NSW this year could continue.
"We know over the coming week, particularly heading into summer as well, we expect more challenging weather," he said.
"We need to keep vigilant. We need to follow the instructions.
"If it's flooded, forget it. You wouldn't drive into a bushfire - don't drive through floodwaters."
Major flooding is expected on the Murray River at Moama and across the Victorian border at Echuca, with flood heights to be as bad or worse than the 1993 flood - the area's second-biggest on record.
The BOM predicts major flooding would begin on Thursday before a likely peak on Friday.
Flood forecasts for the border towns are being updated as upstream peaks are observed.
Residents at a Moama caravan park were told to evacuate by 9am on Monday, while about 200 people in the nearby Indigenous community Cummeragunja had until noon.
Further north, Mathoura residents east of the Cobb Highway running through town have been told to evacuate by 10am on Tuesday before evacuation routes are expected to be cut off.
Another storm system is forecast to develop over central Australia on Tuesday, bringing widespread falls of 25 to 50 millimetres and thunderstorms across inland NSW.
Major flooding at Warren, west of Dubbo, is expected to continue and more rain could cause further rises on the Macquarie River, threatening more severe flooding at Wellington and Narromine in the coming days.
The Riverina region's Murrumbidgee River is likely to reach major flood heights on Tuesday at Narrandera, where residents were told to evacuate over the weekend.
The river has passed the minor flood level at Balranald and Wagga Wagga.
Major flooding is expected to reach Hay on the weekend.
The Insurance Council of Australia has declared the flooding in NSW, Victoria and Tasmania a significant event, beginning to collect claims and opening a hotline to assist policyholders.
The council's chief executive Andrew Hall said the latest floods are still unfolding, but the number of claims is likely to climb.
"Insurers have significantly increased their claims team resources as the entire La Nina event has continued across the year," Mr Hall said.
