La Niña has begun to weaken after helping to make 2022 the ninth-wettest year on record, but the climate driver isn't disappearing quietly.
Australians in the past week have lost access to food and water and access to their towns, and some have even lost their animals and homes.
Heavy rain over some parts of the country has fallen on already saturated catchments during Australia's third La Niña in a row, and after a year of national rainfall that was 25 per cent above the 1961-1990 annual average.
"The year was characterised by wetter-than-average conditions across much of eastern Australia," a summary from the Bureau of Meteorology (BOM) said on Friday.
"Climatologically, these conditions were consistent with the wet phase of natural climate variability for our region — namely a La Niña, a negative Indian Ocean Dipole in winter and spring, and a persistently positive phase of the Southern Annular Mode from mid-autumn."
The wet weather has been welcomed by some, and wreaked havoc for others.
Evacuation orders in recent weeks advised people to flee from rural towns across Queensland, New South Wales, Victoria — where thousands of dead carp are now washing up at Cohuna amid a muddy clean up.
The Northern Territory, Western Australia and South Australia are yet to determine the full impacts of flooding, which is still posing an ongoing threat to safety.
What is fuelling so many floods?
There are several climate drivers impacting different parts of Australia.
While La Niña has brought periods of relentless rain, and drenched soil across Queensland, New South Wales and Victoria, its impacts are felt only in the eastern two thirds of the country.
In the north, it is monsoon season and BOM forecaster Jonathan How says that is coinciding with former tropical cyclone Ellie, bringing large rainfall totals.
Mr How said a wet few years in the east, and huge totals over a few weeks in the north, meant the soil was struggling to absorb any more water.
"The good news is that the climate drivers are starting to weaken … La Niña is starting to weaken," Mr How said.
"The idea is that it will return to a neutral phase … some time in the next month or so and, for eastern Australia, that means a decrease in above-average rainfall.
"Across northern Australia, this is typically the wettest time of the year and, regardless of whether we exit La Niña, we're still expecting an above-average cyclone season in terms of the number of cyclones."
A negative Indian Ocean Dipole also has contributed to higher rainfall, but it has returned to a neutral setting.
The Southern Annular Mode (SAM) index has been strongly positive for the past fortnight and is likely to remain positive until at least mid-January.
In summer, a positive SAM increases the chance of above-average rainfall for parts of north-east Tasmania, eastern Victoria, eastern New South Wales and south-eastern Queensland.
Tropical low causing trouble for territory
Former tropical cyclone Ellie crossed the Northern Territory coastline late on December 23 as a category one system.
Although it was downgraded to a tropical low the next morning, the system brought hundreds of millimetres of rain, sparking flood warnings, and wind gusts of up to 110 kilometres per hour.
Flash flooding prompted calls for assistance in the remote town of Timber Creek and its surrounding communities, about 600km south of Darwin, where authorities described the situation as a one-in-50-year event.
However, the deluge made surrounding roads impassable, cutting off the area and hampering rescue efforts.
An emergency situation was declared and residents of several Indigenous communities had to be evacuated after houses there were submerged or access to drinking water and food were lost.
Those residents were initially taken to a basketball court in Timber Creek, with some spending several days there, then on to a nearby workers camp and defence housing facility.
It took about a week before some of them could return home, due to problems with water supply and sewerage in their communities.
Timber Creek resident and traditional owner Lorraine Jones described the flooding in the region as the worst she had seen in her lifetime.
"It's just a disaster really," she said. "It went through the cemetery and all went underwater. It's a bit sad, my dad is buried there, my grandmother, my uncle."
She said that, with the area cut off, it had fallen to residents — including her brother — to step in and help save their fellow community members.
"He was the only one saving lives. We would've lost probably five kids and a couple of adults," she said.
The former tropical cyclone also caused "slight" freight delays, disrupted tourists' travel plans and drenched stations in much of the territory.
Meanwhile, a "vigorous monsoon" in the Northern Territory's Top End just before New Year's Eve prompted a severe weather warning.
The system — which was forecast to bring up to 80mm of rain in some areas and damaging winds of up to 90kph — led to the cancellation of Darwin's main New Year's Eve event, a concert set to feature Birds of Tokyo.
Monsoonal conditions have been continuing across the region for the past week.
Rainfall from both weather systems have seen Darwin's main dam overflow, for only the second time in nearly five years.
With former tropical cyclone Ellie moving east and through the Northern Territory this weekend, there is now a flood warning in place for the western inland and central territory.
The BOM's NT office has warned that river and creek water levels could rise, roads could become impassable and some communities and homesteads could be cut off.
However, the former cyclone has been forecast to disperse early next week.
Western Australia's 'worst ever' flooding
Frustration is building among people left stranded in the Kimberley region in Western Australia as "the worst flooding event the state has ever seen" hampers evacuation efforts and leaves locals without essential supplies.
Former tropical cyclone Ellie has caused significant property damage and livestock losses in Fitzroy Crossing, about 400km east of Broome, where the river has risen to record levels, cutting the area off from the rest of the country.
The defence force was brought in to help evacuate vulnerable people to Broome and Derby, using helicopters after wild weather grounded commercial flights, but many evacuated residents have been left stranded in evacuation centres with limited supplies.
Fitzroy Crossing residents were anxiously waiting to hear whether they would need to flee, however, floodwaters were expected to recede.
Authorities are waiting for water levels to drop before they can properly assess the Fitzroy Bridge, which is crucial to getting supplies into the town as it is the only sealed highway connecting the West and East Kimberley.
Conditions in Broome were expected to ease on Friday when the town's airport was expected to reopen.
Joe Ross, 62, is from the community of Darlngunaya, home to about 80 people, just metres from the Fitzroy River.
Mr Ross stuck it out until Monday, when the river reached 14.5 metres and water started coming through the floor of the old post office building.
He then headed, with his adult daughter, to the Fitzroy Crossing evacuation centre by boat.
Mr Ross is frustrated by what he says was a lack of coordination around relief efforts.
He said the response from the Department of Fire and Emergency Services had been inadequate to cope with the trauma of a displaced community.
"It's basically getting people to understand that people are traumatised," Mr Ross said.
"You've got to be able to listen to them. You've got to be able to acknowledge them … You've got to respond to the issues."
Mr Ross anticipates a long wait before he can head home.
"This flood is no ordinary flood," he said.
"We're looking at this flood being around for the next few weeks at this height then slowly [goes] down.
"We're looking at not being able to get to our community for the next four to six weeks.
"A lot of these houses are managed by the Department of the Communities.
"They couldn't send people back unless they've been assessed for sewerage, drinking water [safety] and also the electrical safety of the houses."
Mr Ross said there had been a lack of communication around housing and accommodation.
"[We're] totally frustrated by the process with DFES and we're calling on the minister [for emergency services, Stephen Dawson,] to pay attention to what's happening here."
Kalyeeda Station manager Lach McClymont said while the family's homestead was not damaged, they were expecting significant livestock losses.
On Thursday, his wife watched helplessly as their son's pony was swept away by a raging torrent of water just 20m from their house.
He said a silver lining in the floods was the "phenomenal amount of collaboration" from the community in the Kimberley, including people who had lost their homes, such as local helicopter operators Dan and Jami Elliott.
"Their actual home is underwater … They've lost their horses. They've lost all their clothes," he said.
"And they're still out, flying in the rain, dropping off hay, picking people up, shifting cattle," he said.
Rivers 'still rising' in New South Wales
Parts of New South Wales' far west remain under emergency warnings and evacuation orders amid rising floodwaters that are yet to peak.
More than 100 properties at Menindee and surrounding areas have been impacted, with about a dozen evacuated and many more damaged and experiencing overflow flooding.
The road network has also been significantly affected.
On Saturday, Premier Dominic Perrottet and Services Minister Steph Cooke took an aerial tour over the Darling River and lakes system.
"Here in Menindee, just last year, we've had 9,000 gigalitres of water into the lakes," the premier said.
"Now, the context of that, that's five times the capacity and 18 times the volume of Sydney Harbour.
"Waters are still rising. There is so much water, it's going to take a long time for that water to recede."
It's expected the Darling River may peak over the weekend, with initial estimates of 10.7 metres — above the 1976 record — now downgraded to 10.5m.
"We're working with Water New South Wales and the [Bureau of Meteorology] to look at the inflows that are coming and working about what the release strategy is for Menindee Lakes and what the impacts will be," NSW State emergency Service Assistant Commissioner Sean Kearns said.
"So, they have warned that it could get to 10.5m But there still is a chance that it could rise to 10.7m."
Water heads south
In South Australia, high flows down the River Murray have been pouring across the border for weeks, after intense downpours in the easterly reaches of the Murray-Darling Basin.
The cause is the huge amount of rain that has fallen in NSW, Victoria and Queensland amid three consecutives years of La Niña.
With catchments already swollen, this year's rain has caused widespread flooding in the Murray and Darling river systems, and the water is now passing into South Australia.
The peak of the flows has now passed through the Riverland, has pushed through the mid-Murray region and is approaching the mouth, where a large amount of dead marine life has already washed up.
At last count, about 3,400 houses had been impacted by flooding, including 393 primary residences, although not all of these properties have water over the floorboards.
It is estimated that South Australia Power Networks has disconnected 3,160 properties due to the risk of flooding so far, a number that could climb to 4,000.
Among the more fortunate local producers is Blanchetown grape grower David Zadow.
His efforts to protect his property have kept the water at bay.
"We weren't sure when it was going to stop," he said of the last few weeks.
"Definitely the last week or so it does feel like we've been on that knife edge where we're not sure – the water just kept rising, kept rising.
"It was just a very unnerving time."
Knowing that water had peaked, he said, had come as a "huge relief".
"Now that it's peaked we know we've done enough to this point. Now it's just maintaining our levees and getting back to our core business of grapes," he said.
Is this the last we will see of flooding this summer?
It's unlikely.
Mr How said while La Niña is weakening, it could still have lingering impacts on Australia's east.
He said the BOM has kept a long-term watch over those areas and would continue to do so.
"It's been a very long period of months and months of flood forecasts, especially given the impacts we've seen on a number of communities in New South Wales, Victoria and South Australia," Mr How said.
"It's high-impact flooding flowing downstream, affecting high population areas."
In the short term, the BOM's focus is on the Kimberley and the Northern Territory.
"Ex-cyclone Ellie has been unusually slow moving," Mr How said.
"We are now expecting to see some flooding develop in parts of inland Northern Territory as ex-Ellie moves through.
"But, of course, flooding takes a lot longer to subside, so we can expect to be dealing with ongoing flooding for a long time."
He said it could take "weeks, if not months" for the water to drain through central parts of the country.
