Southeast Queensland is set to cop a drenching with more than 200mm of rain forecast as a huge slow-moving cold air mass settles in for the weekend.

December 12, 2020

Southeast Queensland is in for a wet weekend with a huge slow-moving cold air mass expected to unleash torrential rain.

More than 200mm of rain is forecast for Brisbane and on the Gold and Sunshine coasts from Saturday, the Bureau of Meteorology says.

Gale-force winds, dangerous swells and surf and flooding are also likely, with the heaviest rain expected on Sunday.

“We could receive December’s monthly rainfall in one day,” meteorologist Ricus Lombard told AAP.

“Damaging winds with gusts up to 90km/h are also possible.”

A severe weather warning for damaging winds, abnormally high tides and dangerous surf is in place from Fraser Island to the NSW border.

A strong wind warning has been issued for mariners from Mackay to the Gold Coast, with gales of up to 40 knots possible.

Big swells up to 4.5m are expected and a flood watch alert is in place for low-lying areas.

“We could exceed the highest tide of the year by a metre,” Mr Lombard said.

“We’ll (likely) get storm surge from the big swell.”

Significant beach erosion in coastal areas is also possible into Tuesday when a new-moon king tide is forecast.

The 1000km-long and growing weather system moved east over the Great Dividing Range on Friday afternoon.

“The system is still amplifying. It hasn’t reached its maturity but it’s already coming across the Darling Downs,” meteorologist Livio Regano said.

“It’s maturing as it moves and will reach peak intensity on Sunday, and when that happens it will be sitting right on top of us.”

Queensland Parks and Wildlife urged people to reconsider plans to visit national parks in the state’s southeast during the wild weather.

There are significant risks to visitors from flooded creeks or falling trees.

“Even usually benign activities such as walking, hiking or mountain bike riding could become extremely dangerous,” Acting Senior Ranger Jessica Rosewell said.

“It’s not only visitors subject to these significant risks … it’s also emergency crews who may have to go out and try to rescue someone if they’ve got stuck because of a flooded creek or a tree comes down on them.”