Tourists snorkel around Upolu Cay on the Great Barrier Reef. Australia has ordered evacuations in the face of Cyclone Ita. File picture: Brian Cassey

Sydney - Residents and tourists on Friday were evacuating parts of Australia's north-east coast, home to the Great Barrier Reef, as the strongest cyclone in three years was poised to hit land later in the day, bringing destructive winds and flash floods.

Cyclone Ita, a Category 5 storm, is expected to make landfall north of the tropical city of Cairns, the Australian Bureau of Meteorology (BOM) said.

Wind gusts of up to 300km/h and torrential rains are forecast, posing a threat to about 9 000 inhabitants, said Campbell Newman, premier of Queensland state, where the storm is expected to hit land.

“Severe Tropical Cyclone Ita... poses a serious threat to communities along the far north Queensland coast,” the weather bureau said.

The storm's projected course should carry it to land on Friday evening, spreading over an area of about 400km, Queensland emergency officials said.

The storm was still classified as a tropical depression when it barrelled across the Solomon Islands late last week, killing at least 23 people near Honiara, the capital, according to the United Nations.

Sugar farmers in Queensland, who grow about 95 percent of the sweetener produced in Australia, are bracing for potential damage to up to seven million tons of cane, industry groups said.

Australia, the world's third-largest exporter of raw sugar, has seen production devastated by cyclones in the past, most recently in 2011, when cyclone Yasi ripped through Queensland, causing estimated losses of A$3.5-billion from damage to property and reduced tourism earnings.

Sugar production in 2014/15 is forecast to total 4.4 million tons, the Australian Bureau of Agriculture and Resource Economics and Sciences said in March, up from 4.2 million harvested in the previous year.

While the cyclone poses a threat to Australian sugar output, beleaguered cattle farmers may benefit from widespread rain after prolonged drought forced farmers to send record numbers of animals to slaughter as grazing land wilted.

The Great Barrier Reef, one of Australia's most visited tourist attractions, stretches more than 2 000km along the Queensland coast and is the world's largest coral reef system.

The Great Barrier Reef has lost half its coral cover in the last 27 years, the Australian government said in a 2012 report, with storms responsible for nearly half of that damage. - Reuters