Major floods hammer northern Australia

A man was missing in raging floodwaters and hundreds of homes were evacuated in northeastern Australia as storms pelted Queensland state Sunday, with the army put on standby as the weather worsened.

Towns and cities devastated by floods in Queensland two years ago which claimed 35 lives were bracing for another devastating inundation as ex-tropical cyclone Oswald hammered the state.

A 27-year-old man was missing after he attempted to cross a swollen creek near Gympie north of Brisbane and a swift-water rescue team lost their boat trying to retrieve him, according to the town's mayor Ron Dyne.

Dyne said a number of people had taken refuge on the roofs of their homes awaiting rescue from the rising waters, with the centre of Gympie expected to flood later Sunday.

"At this stage, we've got major concerns," said Dyne.

"Everything's occurred rather rapidly given the amount of rain we've had."

A woman was airlifted to safety in Biloela, about 600 kilometres northwest of Brisbane, after spending eight hours in floodwaters clinging to the branches of a tree.

Also in the north, major flooding was expected in the towns of Bundaberg and Gladstone, with hundreds of homes and businesses at risk, some of which had only just been rebuilt following the 2011 floods.

At least one international flight was diverted from Brisbane to Sydney due to the high winds, and Qantas has cancelled a number of domestic services.

About 900 homes had been evacuated in the Gladstone region and about 100 backpackers were sheltering in a community centre at Rainbow Beach after being removed from Fraser Island, according to Dyne.

Queensland Premier Campbell Newman said the army was on standby to assist in the unfolding emergency.

"The challenge now is that we've got multiple events going on," Newman told reporters, adding that he had spoken with Prime Minister Julia Gillard.

"It's likely that we're going to need members of the Australian Defence Force to help with both potentially rescuing people or protecting people, but certainly with clean-up operations."

The weather bureau said there had been damaging winds and reports of "possible tornado activity" throughout southeastern Queensland overnight and warned that further storms were likely.

Disaster management officials said there had been more than 800 emergency calls in the 24 hours to 5am on Sunday, mostly for lost or damaged roofs or requests for sandbags to protect property.

Cyclones and floods are common in Australia's northeast during the warmer summer months. A massive inundation of Queensland in 2011 killed 35 people and brought Brisbane to a standstill for several days, swamping some 30,000 homes.