All eyes are on the sky and oceans as La Niña relinquishes its grasp after three long years, but two experts have warned more catastrophic conditions could replace the weather event and have urged Australians to "be ready".
The Bureau of Meteorology (BoM) issued an El Niño watch just over a week ago, saying there's around 50 per cent chance the brother phenomenon to La Niña could form before summer.
But the research director for CSIRO's Climate Intelligence Program said Australians need to "be ready" for a bad bushfire season – regardless of whether El Niño develops or not.
READ MORE: La Niña is finally over
"It doesn't matter if we have El Niño, summer means bushfire risk for Australia and we need to get ready," Dr Jaci Brown said.
"We've had three years of good rain, which means good growth. There's lot of trees about, so if it did get hot and dry there's lots of load there for fires."
El Niño occurs when the warm water that's normally off the east coast travels to the eastern part of the Pacific.
This takes the energy for rainfall with it, causing drier and hotter conditions across much of the globe – and Australia.
During an El Niño year temperatures typically increase by about 0.2C, while they fall by the same amount during La Niña.
READ MORE: What is behind NSW lake's great disappearing act?
Brown explained climate change is exacerbating the events, adding even a "mild" event could be hotter and drier than what has been previously recorded.
"The concern is there is also climate change happening in the background, so if we do have an El Niño it's going to be hotter and drier than what it would have been," she said.
Those sentiments were echoed by New South Wales Rural Fire Service (NSW RFS) Commissioner Rob Rogers, who fears this fire season could rival Black Summer.
The factors that have fire bosses most concerned
A total of 33 people lost their lives in the 2019/2020 fires, which burned across five states; NSW, Victoria, Queensland, South Australia and Western Australia.
Smoke from the bushfires were linked to the deaths of an additional 450 people, a royal commission heard.
Three billion animals are estimated to have died, 24 million hectares of land was burnt, and 3000 homes were lost.
READ MORE: Man trapped inside firestorm describes harrowing battle to save home
Should a drying period proceed the next fire season, Rogers said one factor will differentiate it from Black Summer.
"Leading into that 2019/2020 fire season we were on the back of a multi-year drought, so there was no grass in the west at all," he told 9news.com.au.
"Now we have grass everywhere and it's not just a little, it's a lot, and the water table is quite high, so it will keep growing.
"We're quite concerned about the potential for bushfires and grass fires mixed together.
"I think it will be quite a difficult fire season."
READ MORE: 'I might not come home': Ex-fire chief recalls terror of 50m-high flames
Adding to the concern is the fact the service is "way behind" on mitigation strategies like burn-offs because of the persistent wet weather.
"We're between 10 – 20 per cent of where we should be," Rogers said, explaining hazard-reduction burns need "goldilocks" conditions.
"It could be too hot, too windy, too cold, too wet; you've got to find that narrow window right in between.
"We'll be doing our best to try and catch up as much as we can but realistically we're not going to be able to catch up before next summer.
"We will prioritise the work we can, but we're just not going to get it all done."
READ MORE: How Black Summer bushfires erupted
He added that virtually "everywhere" in the state is at risk this summer.
"The other problem we have is there are areas, say all around Sydney, that didn't burn at all during those Black Summer fires," he said.
"You've got the northern suburbs, Gosford area, Hornsby, the Hills, Sutherland; all of those areas didn't burn.
"There's quite a lot of fire potential."
One memory still haunts Rogers from the catastrophic fire season of 2019/2020.
"The memory for me is when we started to lose lives, and then firefighter lives as well," he said.
"That's what firefighters do everything to try and prevent. That's when it becomes very difficult.
"That fire season just was beyond."
READ MORE: Dangerous storms bearing down on Melbourne, city bracing for flash flooding
When will we know if El Niño will form?
It will be some time before we have a clear picture of whether Australia will have an El Niño summer.
Forecasters have to closely analyse factors like sea temperatures and wind patterns on the ocean's surface to determine whether the event will form.
READ MORE: Flash droughts on the cards in 2023
"It's not until winter that we'll know what phase it's going into next," Brown said.
"We've got a very delicate system that could be switched either way."
Australia's fire season "officially" starts in October – but fires normally start burning on the North Coast around August and September.
Have a story? Contact Raffaella Ciccarelli at rc*********@******om.au.
Sign up here to receive our daily newsletters and breaking news alerts, sent straight to your inbox.
