Brisbane properties at risk of flooding as Cyclone Alfred bears down

“The modelling the councils are doing at the moment is to factor in a storm surge over and above what the high tide is,” he said. “As the system gets closer, that will be communicated.”

In light of a 7-metre wave off North Stradbroke Island, Crisafulli said Cyclone Alfred was a serious system.

Residents across the south-east, including Brisbane and the Gold and Sunshine coasts, continued to join hours-long queues for sandbags for their homes and businesses late into Tuesday.

And more than 400 police recruits were being made available to doorknock homes to help residents prepare.

The Port of Brisbane was closed to freight, while Brisbane Airport remained on high alert, with the possibility of flights being rescheduled or cancelled due to destructive winds. Qantas and Virgin said they would allow customers to rebook flights free of charge or claim a credit.

Meteorologist Sue Oates said the destructive winds would be more than 95km/h, with gusts of 130km/h.

But she said the stronger winds would be closer to the system’s centre, so some areas would be worse hit than others.

“Where that system centre is, there is still a broad area of uncertainty, but within that region from Sandy Cape through to the Queensland border,” Oates said.

She said the community needed to remain aware of the warnings, with the 90km/h gusts to reach exposed coastal areas by late Wednesday.

“As the system moves closer towards the coast – and at this time, it looks to be approaching the coast late on Thursday into early Friday morning – those winds will continue to increase within the tropical cyclone centre to destructive force winds,” she said.

Rainfall totals of up to 400 millimetres could not be ruled out, Oates said, which was expected to continue into Saturday, causing a three-day total of about 700 millimetres.

She said while the cyclone would need to develop significantly to become a category 3, the weather bureau could not rule out that possibility. However, she said under the current modelling, a category 3 was not expected.

Gold Coast Acting Mayor Donna Gates said the city was preparing for a worst-case scenario, with a disaster flood risk map showing some suburbs could be significantly affected, including parts of Surfers Paradise, Elanora and Paradise Point.

The bureau has been forecasting intense winds on the southern side of Cyclone Alfred.

Meanwhile, the Queensland government amended regulations in 21 local government areas to enable supermarkets to restock shelves 24/7 as panic buying continued.

Crisafulli reminded the community that the isolation that had occurred during floods and cyclones in far north Queensland were not an issue in the south-east due to better access.

Wivenhoe and Somerset dams were also being closely monitored by authorities, but releases before the cyclone were unlikely.

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