As south-east Queensland and northern New South Wales prepare for Tropical Cyclone Alfred to cross the coast, an Australian researcher explains what makes this system so unusual.

Australia's east coast braced on Wednesday for a tropical cyclone that is swirling towards Brisbane, the country's third-most populous city, as authorities warned thousands of properties were at risk due to strong winds and flash flooding.

A large swathe of Australia’s east coast is preparing for strong winds and life-threatening flooding as a tropical cyclone is forecast to make landfall around the nation’s third-largest city.