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What we know about Tropical Cyclone Marcia:
• Cyclone Marcia has damaged homes in Yeppoon
• The storm is now over Rockhampton and 250km/h wind gusts have caused damage to houses.
• Marcia was a category four storm when it crossed the coast at Yeppoon earlier today.
• It's since been downgraded to a category three storm and as of 1pm (AEST) was hitting the city of Rockhampton, to Yeppoon's south.
• So far there are no reports of deaths or serious injuries in either location.
Two powerful cyclones roared ashore in Australia today leaving a trail of destruction with buildings severely damaged, trees uprooted and power lines downed, cutting electricity to thousands of people.
Tropical Cyclone Marcia slammed into the Queensland with its landfall coming just hours after a second big storm -- Cyclone Lam -- hit further north.
Follow live updates here and at the bottom of this article.
The category four Lam caused extensive damage to remote Aboriginal communities near Elcho Island, some 500 kilometres east of Northern Territory capital Darwin, including Milingimbi, Ramingining, and Gapuwiyak.
You know how people say it sounds like a freight train? This sounds like 100 freight trains.
"Initial indications are that there has been substantial damage, initial reports are the airstrip is still intact but covered with debris," regional police commander Bruce Porter said of the Elcho Island community, which was without power and water.
"There are downed power lines. There are a number of trees down and many roads are impassable and we do have a number of buildings and houses that have been severely damaged."
He added that reports suggested structural damage in Milingimbi and Ramingining but Gapuwiyak appeared to have escaped the worst. There were no reports of major injuries.
Further south, howling winds and torrential rain had residents hunkering down to wait out the terrifying conditions whipped up by Marcia with authorities warning of a "calamity".
The storm landed near Shoalwater Bay, north of Yeppoon, a town of 16,000 people some 670 kilometres north of Brisbane. It has since been downgraded to a category four.
My message to all of Rockhampton residents is please stay indoors. The eye of this storm is headed directly towards you.
Officials earlier forecast Yeppoon to bear the brunt of the storm's eye but Queensland Premier Annastacia Palaszczuk said it only "grazed" the town and was now heading for much bigger Rockhampton, home to some 80,000 people.
"We have heard that there has been some trees down and some slight damage to houses," she said of Yeppoon, adding that there was flooding and 30,000 people without power in the area.
"My message to all of Rockhampton residents is please stay indoors. The eye of this storm is headed directly towards you," added the premier, who was only been in the job officially since last Friday.
Rockhampton is an older town with many structures not built to withstand a cyclone, warned Steve Turton of James Cook University, an expert in Queensland cyclone history.
The impact of Marcia was being felt over a wide area with residents as far away as Brisbane sandbagging their homes and clearing yards of objects that could be whipped away by the wind.
More than 60 schools have been closed and businesses shuttered and a series of domestic flights were cancelled, mostly in and out of Gladstone, Rockhampton, Mackay and Bundaberg.
Massive seas, a deluge of rain, and gusts of up to 295 kilometres per hour were being experienced along the central Queensland coast with a storm surge predicted to raise sea levels three metres higher than normal.
"We've got trees all around us and it sounds like jumbo jets flying all around the top of us. All the trees are starting to fall over," said a man identified as Ted, who called the Australian Broadcasting Corporation from his home in Byfield.
Resort operator Sian Appleton said Great Keppel Island off Yeppoon expected serious damage.
"I think we'll probably lose three cabins and maybe even some of the bistro area."
Queensland Police Commissioner Ian Stewart said it was a "desperate situation".
"This is going to be a calamity, no doubt about that," he said ahead of Marcia making landfall.
Queensland has been smashed by several major storms and cyclones over the past few years with Cyclone Oswald, also a category five, flooding parts of the state in 2013, racking up insurance claims of some Aus$977 million.
High waves battering the shore at Yeppoon:
The Queensland government has opened a community recovery hotline as Cyclone Marcia continues down the state's central coast.
Financial assistance is yet to be activated however the hotline (1800 173 349) will provide useful information about the assistance available, Communities Minister Shannon Fentiman said.
It's for residents who are not in a life-threatening situation but need information.
"Our first priority is caring for vulnerable people who are in the path of TC Marcia," Ms Fentiman said.
"Our officers are contacting families who are known to the department and our community partners are also contacting their clients to ensure they have the support they need."
Those whose lives are at direct risk should contact triple zero or the SES (132 500) for storm and flood assistance.
Residents can also download a phone app called Self Recovery that will provide vital tips for disaster preparedness and what to do after a severe event has hit their region.
• Cyclones are low pressure systems that form over warm tropical waters, with gale force winds near the centre. The winds can extend hundreds of kilometres (miles) from the eye of the storm.
• They are also known as hurricanes or typhoons, depending on where they originate in the world, when they reach sustained winds of 119 kilometres per hour or higher. Tropical cyclones are common in Australia's northeast and northwest during the warmer months, with the season running from November to April.
• Australia uses a different scale to the rest of the world when rating the intensity of cyclones. They are categorised from one to five, with five the worst. A category five has gusts of more than 280 kilometres per hour and is extremely dangerous with widespread destruction.
• A five also produces heavy rainfall with flash flooding and massive seas. Storm surges when the cyclones reach land raise domes of water of about 60-80 kilometres across and about two to five metres higher than the normal tide level.
• Category fives Oswald in 2013 and Yasi in 2011 caused serious flooding damage in parts of Queensland and raked up billions of dollars in insurance claims. The worst cyclone in Australia was Tracy, which hit Darwin on Christmas Day in 1974, killing 65 people and flattening more than 90 per cent of the northern city's homes.
A storm surge is a rise above the normal water level along a shore as a result of strong onshore winds and/or reduced atmospheric pressure.
It's often associated with a tropical cyclone that makes landfall. In non-tropical areas it can be formed by intense low-pressure systems.
A storm surge is usually about two to five metres higher than the normal tide level.
Their height is determined by a number of factors: cyclone intensity, speed and the angle it crosses the coast; the shape of the sea floor; and topography.
Storm surges are most dangerous when they occur at the same time as a high tide. This is known as a 'storm tide'.
When this happens, typically safe areas can be affected. Sea water flooding can extend along the coast for more than 100km and inland for several kilometres.
These conditions are usually made worse by large waves produced by strong winds.
Most casualties during tropical cyclones occur as the result of storm surges.
• In 1970, the Bay of Bengal off India was hit by Bhola Cyclone and a severe storm surge that killed up to 500,000 people.
• In 2008, a storm surge caused by Cyclone Nargis in Myanmar led to the deaths of more than 138,000 people.
• In 2013, the Philippines was struck by Typhoon Haiyan, which resulted in severe flooding and killed more than 3600.
First, find out if you live in a surge-prone area and if you do, have a pre-determined place to which to retreat in the event of a storm surge.
Also find out where your nearest safe high ground is and the safest way to get there.
Have an evacuation plan that includes what medicines you might need to take with you, as well as important documents, and how to rescue pets.
In the event of evacuation, if you choose to leave of your own accord, make sure you let your neighbours know.
Always listen to Bureau of Meteorology weather warnings so you're aware if conditions worsen.
- AFP, AAP, AP
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