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As Tropical Cyclone Alfred barrels toward Australia’s eastern coast, residents from Brisbane to northern New South Wales are bracing for a storm event not seen in over half a century.
The cyclone, currently a Category 2 system, is expected to make landfall between Noosa and Coolangatta, north of Brisbane, late on Friday or early Saturday, bringing destructive winds, life-threatening flooding, and coastal erosion to some of Australia’s most densely populated areas.
According to the Bureau of Meteorology, Alfred could possibly reach a Category 3 status but the chances of that remain low. However, the storm was expected to remain on the stronger end of Category 2 when it makes landfall.
Click here for live updates on Cyclone Alfred
That means winds of up to 150kmph per hour will be battering areas of Queensland and NSW, with rainfall totals expected up to 600mm, enough to swell up rivers and create flood risks in a wide, highly populated region.
Queensland premier David Crisafulli called Cyclone Alfred an “extremely rare event,” as he urged residents to pay heed to warnings.
The last time Brisbane saw a tropical storm reach this close to its shores, it was 1990. Gold coast acting mayor Donna Gates said in terms of destructive winds and heavy rain, the city hasn’t seen anything like this since 1952.
But it’s not just the size of the storm that is concerning experts – it’s how it has been moving.
Most cyclones that form in the Coral Sea follow a typical pattern: they track southeastward, away from the Australian coastline, as they get caught in mid-latitude westerly winds.
But Alfred has done the opposite. It initially moved out to sea southwards, travelling parallel to Australia’s east coast, and then took a sharp turn westward towards Australia’s eastern coast.
Dr Liz Ritchie-Tyo, a professor of atmospheric sciences at Monash University, explains that this shift is due to Alfred’s interaction with a mid-latitude trough – a system of low pressure that extended northward and altered the storm’s movement.
“When tropical cyclones interact with a mid-latitude trough, they undergo a process called extratropical transition,” she says. “During this process, they can re-intensify into a hybrid system, sometimes even stronger than the original tropical cyclone.”
Now, as the mid-latitude trough moves east, Alfred has been left under the influence of the subtropical ridge, which is pushing it westward – straight toward Australia’s southeast coast.
“This sharp westward turn is unusual,” she said.
Historically, tropical cyclones tend to weaken before reaching southeast Queensland and northern New South Wales due to cooler waters and wind shear – changes in wind direction and speed that can break apart a cyclone. But that’s not happening with Alfred.
“Tropical cyclones are normally contained to north of the 25-degree parallel, yet we are now seeing them track further south,” says Dr Tom Mortlock, head of Climate Analytics Asia-Pacific.
“The last severe cyclones to make landfall near Brisbane were Dinah in 1967 and Wanda in 1974. The 1954 cyclone, which caused the ‘Great Flood’ in northern NSW and southeast Queensland, is the best historical comparison.”
The fact that Alfred is expected to maintain Category 2 intensity when it crosses the coast suggests that oceans are warm enough to sustain tropical cyclones much further south than usual.
Warm ocean waters – above 26.5C – and low vertical wind shear are essential for a cyclone to develop, strengthen, and sustain itself. Climate crisis affects both.
Currently, the water off the coast of Sydney has a temperature of 27C, about 1C above average. Rising global temperatures, driven by burning coal, oil and gas, are increasing sea surface temperatures across the planet, increasing marine heatwaves and fuelling hurricanes and cyclones.
In fact, when Alfred developed in late February, it formed alongside two more systems. While it is not unheard of for two or three tropical cyclones to form out of the same trough, it is rare in the South Pacific.
“Tropical cyclones are clearly linked to global warming. Scientists have been pointing this out for years, and we are now seeing evidence in real time – stronger storms, reaching further, impacting a larger area,” Dr Iftekhar Ahmed, associate professor the University of Newcastle.
“This is a problem we are seeing worldwide,” Dr Mortlock adds. “Right now, ocean temperatures are warm enough to sustain tropical cyclones as far south as Sydney, which is highly unusual.”
This year’s Atlantic Hurricane Season also saw an extraordinary number of storms with 11 of the 18 developing hurricane strength and five becoming major hurricanes. When Hurricane Milton devastated Florida, scientists found “bath-tub hot” waters off the coast drove its intensification.
Another major concern is Alfred’s slow movement. The cyclone is currently traveling at 14kmph, but there were concerns it could get slower than the average tropical cyclone, which typically moves between 15-20 kmph.
Several tropical storms in recent years have been moving slowly, which gives them more time to intensify and if the system passes slowly over cities it bring more rainfall.
“The system is staying over the ocean longer, meaning it has more time to feed on warm waters, intensify, and maintain its strength before landfall,” meteorologist Thomas Hinterdorfer told The Courier-Mail.
“We would much prefer a cyclone to come through faster,” he said.
Scientists warn that while tropical storms have always been devastating, climate crisis is making them stronger, more frequent, and more unpredictable.
“We need to start planning for a future where these types of storms become more common,” Dr. Ahmed says. “This isn’t just a one-off event – this is the new reality.”
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