Early wind and rain from a rare tropical cyclone began lashing part of eastern Australia on Thursday as schools were closed, public transport was stopped and desperate residents got around shortages of sandbags by buying potting mix.

Tropical Cyclone Alfred is forecast to cross the Queensland state coast somewhere between the Sunshine Coast region and the city of Gold Coast to the south early on Saturday, Bureau of Meteorology manager Matt Collopy said.

Between the two tourist strips is the state capital Brisbane, Australia’s third-most populous city which will host the 2032 Olympic Games.

“The wind impacts, we’re already seeing those start to develop on the exposed locations along our coast with gusts reaching 80-90 kph. We are expecting those to continue to develop,” Collopy told reporters in Brisbane.

Alfred is expected to become the first cyclone to cross the coast near Brisbane since Cyclone Zoe hit Gold Coast in 1974 and brought widespread flooding.

Cyclones are common in Queensland’s tropical north but are rare in the state’s temperate and densely-populated southeast corner that borders New South Wales state. More than four million people lie in the cyclone’s path.

Alfred was 280 kilometres east of Brisbane and moving west on Thursday with sustained winds near the centre of 95 kilometres per hour, and gusting to 130 kilometres per hour, Collopy said.

The storm is expected to maintain its wind strength before hitting land.

But the greatest fears are for the expected flooding over a wide area.

Modelling shows that up to 20,000 homes in Brisbane, a city largely built on a river floodplain, could experience some level of flooding.

Prime Minister Anthony Albanese said 660 schools in southern Queensland and 280 schools in northern New South Wales were closed on Thursday as weather conditions worsen.

The federal government had delivered 310,000 sandbags to Brisbane and more were on the way, Albanese said.

A shortage of sandbags in Brisbane, a city of more than three million people, led some to buy sacks of potting mix as an alternative, according to Damien Effeney, a chief executive of a rural supplies business. (AP)