A Queensland man has died in flash flooding while one of Australia's biggest music festivals has been forced to cancel performances as a powerful weather system batters the east coast.
The man's body was found by police on Friday morning in floodwaters near Sandy Creek at Nanango, about two-and-a-half hours northwest of Brisbane.
Emergency services responded to reports of a car swept into floodwaters about 5:30am before the 47-year-old was found three hours later.
Queensland Premier Annastacia Palaszczuk said the man's death was "tragic" and urged Queenslanders to stay away from the water this weekend due to the hazardous weather.
The death follows the rescue of a number of people "in quite a dangerous situation" on the roof of a car at nearby Kingaroy, Queensland police said.
Flash flooding is affecting the South Burnett region and drivers are being urged to stay off roads.
Meanwhile, Friday's performances on the main stages of the Splendour in the Grass music festival at Byron Bay have been cancelled.
Day ticket holders are being asked not to attend the festival while repairs are carried out.
"We ask for patience while we work through the refund process," a statement from the festival organisers said.
"We look forward to Saturday and Sunday programming moving ahead as planned."
Thousands of music fans have faced long queues to access the muddy campgrounds.
Punters reportedly waited 12 hours to enter the site as heavy rain hit, with some forced to sleep in vehicles.
In Queensland, there are minor flood warnings in place for parts of the Stanley, Mary, Burnett and upper Brisbane rivers after overnight rainfall totals of between 80-120mm.
Damaging winds averaging around 50km/h are possible in exposed parts of the coast. Peak gusts may reach 110km/h on Fraser Island, also known as K'gari, forecasters say.
The low-pressure system is expected to move south on Friday and Saturday, and beaches have been closed on the Gold Coast due to the dangerous conditions.
The Bureau of Meteorology has also issued a severe warning for damaging surf for the Byron, Coffs Coast, Macquarie and Hunter coasts.
A gale warning for the Byron coast is also in place, with waves of more than five metres possible for northern NSW before conditions begin easing on Saturday afternoon.
"Beach conditions in these areas could be dangerous and people should stay well away from the surf and surf exposed areas," the bureau said.