Tropical Cyclone Alfred intensifies as latest forecast predicts landfall just north of Brisbane | Australia weather

Forecasters say there is now increased certainty that Tropical Cyclone Alfred will hit the heavily-populated south-east Queensland coast in the coming days, as the storm’s potential track “narrows”.

Alfred was upgraded to a category two cyclone early on Tuesday.

The Bureau of Meteorology said that coastal communities in and around Brisbane could experience wind gusts up to 100km an hour as early as Wednesday, and single-day rainfall totals of up to 400mm later in the week.

Updated tracking maps from the BoM on Tuesday forecast Alfred potentially making landfall just north of Brisbane on Thursday night or Friday morning.

The forecast track would represent a nightmare scenario for authorities in the Queensland capital, a city with 2.5 million people and susceptible to severe flooding. The bureau said most of the intense rainfall will occur to the south of where Alfred makes landfall.

But tracking maps may change again over the coming days as the forecast evolves.

The Queensland premier, David Crisafulli, said on Tuesday the “area of interest has narrowed” to a stretch of coastline that includes the Sunshine Coast, Greater Brisbane and the Gold Coast.

“[That is] a largely populated area and we’re asking Queenslanders to stay on their guard,” Crisafulli said.

“The cyclone has firmed. All of the information does show this is something we need to take seriously.

“We’re asking a large part of the population, in a pretty big area, to be ready. There is still an element of the population that hasn’t yet fully understood the magnitude of this system. It’s been many decades since Queensland has been here. I know the people in the south-east might not have experienced a cyclone before.”

More than 4 million people – from Grafton in New South Wales to K’gari in Queensland – remained on a formal “warning” footing by the bureau.

Early on Tuesday morning, Alfred was 560km east of Brisbane and moving away, to the south-east, about 6km/h.

But forecasters said with increasing confidence they expect the system to undergo a “recurvature” by late Tuesday afternoon – a sudden change of direction – as it bumps up against another weather system to the south.

“Models are in agreement that the strengthening mid-level ridge to the south to steer Alfred westwards from later today,” the bureau’s technical bulletin from Tuesday morning said.

“Landfall location could range from the Sunshine Coast to the Gold Coast, and there is also uncertainty in terms of the timing of coastal crossing between late Thursday and Friday morning.”

The update says the nature of the cyclone means it is difficult to predict its intensity when it reaches landfall.

There are three main causes of concern: surf conditions and coastal erosion; damaging winds; and potential flooding,

Crisafulli said the severity of the system, and the timing of it crossing the coast, would be critical.

“If it crosses at high tide, it makes it a far more challenging prospect,” he said

Sue Oates from the Bureau of Meteorology said there was “total consensus” from seven global models that Alfred would head back towards the coast.

Oates said strong winds – potentially more than 90kmh – could be recorded in coastal communities from Wednesday. There was also a significant risk of riverine flooding following predicted very intense rainfall.

“As Tropical Cyclone Alfred continues to move closer to the coast, rainfall will move further inland and become more intense, and we’re likely to see daily rainfall totals of around 200mm-plus with isolated totals even higher than that, and up around 400mm is not out of the question,” Oates said.

“This will continue into Friday and looks like at this stage Saturday will still be significantly wet for South East Queensland.

In the suburbs of south-east Queensland, residents have begun preparations.

Brisbane has severely flooded three times in the past 15 years. Unlike parts of northern Queensland, locals do not typically prepare for the possibility of a cyclone. Many older “Queenslander” homes, an architectural feature of the area, are timber-built from the early 1900s.

Those risks have prompted authorities to issue clear early warnings.

“Early preparation can reduce damage and increase safety,” said Andrew Gissing, the chief executive of Natural Hazards Research Australia.

“Research … shows that often people do not understand what they need to do to be fully prepared. For example, research after the 2022 floods in Queensland and New South Wales found that 50% of residents acknowledged that they could have been more prepared.”

Gissing said the primary hazards associated with cyclones were flooding, strong winds and coastal erosion, and that these occurring in a densely populated area were of “significant concern”.

“The damage that Alfred could lead to includes damages to homes, businesses and infrastructure; disruption to essential services and supply chains; agricultural losses; and injury and fatalities,” he said.

“Significant coastal damage can occur without a cyclone making landfall because of abnormally high tides and damaging surf.”

Gissing said homes older than 1980 might not be built to building codes and could be at particular risk to strong winds.