By Melanie Vujkovic, ABC news
Cyclone mapping taken from Windy.com detailing conditions as of 2pm on Tuesday. Photo: Supplied/Windy.com
More than 4 million people are in the firing line of Tropical Cyclone Alfred as it tracks towards the south-east Queensland and northern NSW coast.
About 20,000 homes in Brisbane alone are at risk of storm surge and flooding impacts associated with the system.
A warning zone now spanning north of the Sunshine Coast down to Yamba has been issued with the category two system forecast to maintain its intensity before it makes landfall late Thursday or early Friday morning.
Police and emergency services have begun doorknocking low lying areas along the south-east Queensland's coastline.
Premier David Crisafulli said it was likely to make landfall north of Noosa to just south of the NSW border.
"So a largely populated area, and we're asking Queensland to stay on their guard," he said.
Brisbane could see major flooding
New modelling shows 20,000 homes in Brisbane could be impacted by Tropical Cyclone Alfred.
Brisbane City Council is warning residents at risk of significant storm surge and flooding to consider relocating.
These 20,000 properties could experience anything from mild inundation in their yards to significant flooding in their homes.
Areas most at risk include Brighton, Windsor, Ashgrove, Morningside, Rocklea, Coopers Plains, Carina, Sandgate, Hemmant, Lota, Tingalpa, Indooroopilly, Albion, Bardon and Wynnum West.
Crisafulli said a flood watch remained from the Mary River all the way down to the NSW border.
"The cyclone has firmed, and all of the information does show that this is something we need to take seriously," he said.
"There is still an element of the population that hasn't yet fully understood the magnitude of this system, and that's completely understandable because it's been many decades since Queensland has been here, in this part of the state."
He said a number of evacuations have already begun for vulnerable people on the islands.
The ADF has been briefed to be on stand-by but currently no formal request has been made by the state.
'Destructive winds'
Sue Oates from the Bureau of Meteorology said in the past 24 hours TC Alfred intensified into a category two system and by Tuesday night was located 600 kilometres east of Brisbane.
She said in the next couple of days, the impact zone could expect winds in excess of 95kph and gusts of over 130kph.
"The mean winds will be confined close to the system centre, so not everywhere in south-east Queensland will receive destructive winds," she said.
"Why we are heading into a tropical cyclone warning this afternoon is because we are expecting gale force winds with gusts in excess of 90 kph on our exposed coastal areas by later Wednesday," she said.
"So that's within the 24 hour period."
Rain to continue into weekend
Oates said what added complexity was that the system was combined with elevated sea levels.
"So abnormally high tides associated with the low pressure of the tropical cyclone system," she said.
"So by tomorrow night, early Thursday morning, we are expecting exceedence of some of the highest tides we will see within the year."
She said the system was expected to bring several days of heavy rainfall most likely from Wednesday to exposed coastal parts.
"The totals that we could probably expect during Wednesday, in a 24-hour period, is some isolated totals up to 100 millimetres, which does not seem like a lot, but as Tropical Cyclone Alfred continues to move closer to the coast, that rainfall will move further inland and become more intense," she said.
"We're likely to see daily rainfall totals of around 200 millimetres plus, with isolated totals even higher than that, and up around 400 millimetres is not out of the question.
"This will continue into Friday, and it looks like at this stage, Saturday will still be significantly wet for south-east Queensland."
PM to land in Brisbane
Prime Minister Anthony Albanese was due to arrive in Brisbane on Tuesday night.
The ABC understands the Australian Government Disaster Response Plan has been activated and a crisis coordination team will be deployed.
The federal government has pre-positioned heavy-lifting helicopters from the National Aerial Firefighting Fleet to support the NSW and Queensland governments.
The Sikorsky S-61 is set to be deployed to Coffs Harbour and a UH-60 Black Hawk will be stationed in Bundaberg.
Australia's National Situation Room continues to monitor the situation on a 24/7 basis.
Treasurer Jim Chalmers, who was in Logan, south of Brisbane on Tuesday, said it would be an "anxious wait" for TC Alfred to cross the coast.
"We know that the communities will be ready when this cyclone crosses the shore," he said.
"But it is going to be an anxious wait.
"We are all bracing for heavy weather. We are prepared for the worst, but we hope for the best."
-ABC
