Thousands of Australians abandoned their homes as a powerful cyclone bore down on coastal towns in Queensland on Monday, March 27, while others ignored authorities' advice to evacuate with winds forecast to reach up to 300 km per hour (185 mph), Reuters reports.

Cyclone Debbie is forecast to strengthen to a Category four storm before it makes landfall in the northeast state early on Tuesday, the Australian Bureau of Meteorology said.

State Premier Annastacia Palaszczuk warned it would be the most powerful storm to hit the country since Cyclone Yasi in 2011, which destroyed homes, shredded crops and devastated island resorts.

About 3,500 people left low-lying townships near Townsville, while authorities advised 2,000 more people in the town of Bowen to also leave, Palaszczuk said, adding that the "window of opportunity to leave is drastically closing" as weather worsens.

"This is going to be a nasty cyclone," Palaszczuk told Nine Network television. "These wind gusts are going to be absolutely huge."

A category five storm is the strongest on the five-step Saffir-Simpson scale of hurricane intensity.

Queensland produces some 95 percent of Australian bananas and while Cyclone Debbie is on course to miss the largest growing regions in the state's far north, analysts said heavy rains and strong winds could cause significant crop damage.