Thousands of people have been evacuated from their homes as a powerful storm approaches Australia's northeast coast.

Cyclone Debbie is expected to turn into a Category 4 storm, the second strongest on the scale of hurricane intensity, before it makes landfall in Queensland on Tuesday morning.

Winds are forecast to reach up to 260 kmph (160 mph) as the storm hits, making it Australia's most powerful storm since Cyclone Yasi in 2011.

Around 3,500 people have been evacuated from low-lying areas near Townsville after concerns that the tidal surge could be as high as 4m (13ft).

Authorities have also advised a further 2,000 people in the town of Bowen to leave their homes and evacuations are under way from low-lying areas in Mackay.


Image: Grey skies in Townsville as the storm approaches the Queensland coast

Queensland State Premier Annastacia Palaszczuk encouraged Queensland residents to listen to authorities, saying that "the window of opportunity to leave is drastically closing".

"I am just pleading to everyone, please, listen to authorities. I do, you must as well. This is about your safety, it is about the safety of your family and the safety of your children," she said.

Ms Palaszczuk said the farming region has never experienced a storm stronger than Category 2 and warned that older homes would not withstand a Category 4 storm.

Queensland State Disaster Co-ordination Centre deputy commissioner Steve Gollschewski told people in the areas affected "to move now".

"Don't wait till tomorrow because you will not will be able to move probably past midnight tonight," he said.

Image: Townsville residents fill sandbags in preparation for Cyclone Debbie

The storm is expected to land somewhere along a sparsely populated 60-mile stretch of coast between the towns of Ayr and Bowen, the Australian Bureau of Meteorology said.

The bad weather is also due to hit the Whitsundays Islands.

Whitsundays Regional Council Mayor Andrew Wilcox said: "in the Whitsundays we're pretty laid back sort of people.

"So what my message is, 'guys, this is a real threat, this is serious, don't be complacent, make sure you have all your preparation right, take shelter and please be safe'."

Operations at several coal mines in the area have been halted ahead of the storm and the Abbot Point coal terminal and ports at Mackay and Hay Point have also closed.

Flights to the region are also affected. Townsville Airport is closed and airlines Qantas, Jetstar, Rex and Virgin Australia say they have cancelled flights in the region.