A "significant disaster event" looms as a tropical cyclone zeros in on a densely populated part of Australia's coast for the first time in 50 years.
However, an expert believes time is on southeast Queensland's side as it prepares for Tropical Cyclone Alfred's impact.
Alfred is expected to make a U-turn towards Queensland's coast on Tuesday before crossing the coast later in the week, bringing destructive winds, heavy rain, flash flooding and significant coastal erosion.
The cyclone is set to hit between Queensland's K'gari (formerly Fraser Island) and the Gold Coast on Thursday or Friday as a category one or two system.
The southeast last copped a direct hit in 1974 when Cyclone Zoe crossed at Coolangatta.
It came just weeks after Cyclone Wanda had triggered record Brisbane floods that claimed 16 lives.
There have been some near misses since with Nancy in 1990 and Oma in 2019.
Cyclones may have threatened the southeast before but an expert warned many more people and significant infrastructure would be "in the firing line" when Alfred hit.
"What we have seen since then (1974) particularly at places like the Gold Coast is a significant amount of development on flood plains and along the coast," Natural Hazards Research Australia CEO Andrew Gissing told AAP.
"It could be a significant disaster event. We are right to be taking this seriously."
People have been warned to leave or prepare for the worst, sparking panic buying in some areas, while others were busy sandbagging as they bunkered down.
But Mr Gissing was confident regions in Alfred's path had enough time to prepare, potentially reducing damage and increasing safety as long as they took the cyclone risk seriously.
He said their research after the 2022 floods that devastated Queensland and NSW showed 50 per cent of residents acknowledged that they could have been more prepared.
A cyclone watch has been issued from K'gari down to Grafton, NSW.
Gale-force winds are expected to develop from Wednesday night, with gusts of more than 90km/h.
Damaging surf and abnormally high tides are set to create dangerous beach conditions, flooding and potential significant coastal erosion before Alfred hits from Thursday night.
"The affects of Alfred will be felt widespread not just near the actual crossing point," the Bureau of Meteorology's Sarah Scully said.
Alfred is set to bring winds strong enough to bring down trees and power lines along with intense rainfall that may lead to "life threatening" flash flooding and a storm surge.
Alfred is set to be downgraded to a tropical low by Friday but rain and flooding impacts are expected to continue, possibly into the weekend.
Flood watches are current across southeast Queensland and NSW's northeast.
