A late change of course by Severe Tropical Cyclone Rusty has spared Port Hedland the full force of 230km/h winds, leaving the tiny community of Pardoo to bear the brunt of what was a category-four monster.

The eye of the massive storm began to cross the West Australian coast on Wednesday afternoon, more than 30 hours after the north-west coastline was placed on red alert and residents told to take shelter and stay inside.

That included the residents of the Pardoo roadhouse and the Pardoo station, about 120km east of Port Hedland, who were the first to feel the force of Rusty.

Ian Badger, manager of the Pardoo roadhouse, sent his staff to Broome earlier this week while staying to face the storm - and the damage - alone.


"I was half confident yesterday we would miss the main centre of it," Mr Badger said.

"I have got trees going over, so there is going to be a fair bit of damage.

"So we will just keep an eye on everything, and sit it out.

"I can't really do too much - it is pretty much horizontal rain."

The residents of Pardoo Station said on Facebook that the homestead had suffered some slight damage, and they were braced for more.

"We are all holed up in the homestead where the walls are so thick that if you closed the curtains you wouldn't even know it was going on!," they said.

"Have lost the roof to our car port and water damage to another building so far."

The storm was downgraded to a category three as it crossed, with Port Hedland experiencing 36 hours of gale-force winds.


Cyclone warnings remained in place from Sandfire Roadhouse to Whim Creek including Port Hedland, Marble Bar, Nullagine, Millstream, Tom Price, Telfer and Newman.

Widespread very heavy rainfall is tipped for overnight and on Thursday, and is likely to lead to major flooding in the De Grey and Fortescue catchments.

Rainfall totals of 187mm at Yarrie were recorded in the 24 hours until 9am, and a further 76mm fell from 9am to 1.30pm.

Figures from NASA satellites tracking the huge storm make for frightening reading, with the TRMM satellite, which flew directly over Rusty on Tuesday, recording an hourly average rainfall of more than 138mm near Rusty's western eye wall.

And a 3D image of Rusty's rainfall and cloud heights created at the Goddard Space Flight Center in Maryland showed the tops of some of the towering thunderstorms in Rusty's eye reaching heights of over 12km.

John Newman, the regional director of the Department of Fire and Emergency Services, said it was vital people stayed indoors until local authorities confirmed the area safe.


"During a red alert there is a threat to lives and properties," Mr Newman said.

"This message seems to fall on deaf ears as we continually encounter people outdoors and on the roads causing a danger to themselves and others."

While WA braced for Rusty, the rest of Australia's weather was also being affected, with cloud from the system streaming across the continent towards Victoria.


Thousands of people were late yesterday locked down ahead of a deadly category four cyclone that had already forced evacuations, closed the world's biggest bulk minerals port and shut down major mines in Western Australia's northern Pilbara region.

Cyclone Rusty's front reaches across about 200km, centred on an eye 65km in diameter.


Winds that had already been battering the coast at up to 120km/h were expected to gust to 250km/h as Rusty crossed the coast last night, driving huge tidal surges expected to cause widespread flooding.

The power of the vast, slow-moving cyclone is expected to last well after it hits land somewhere between Port Hedland and Pardoo to the north, with gale-force winds, pounding seas and floods likely to trap people indoors and sever road and rail links.

"This is a nasty system," Neil Bennett of the Bureau of Meteorology told ABC radio.

"It's going to lead to issues with flooding, roads being cut, structural damage, powerlines are likely to be down and add that to the water everywhere and that's going to be a dangerous environment for people to be moving around in."

Authorities warned that Rusty would not follow the normal pattern of short-lived tropical cyclones. Its snail-like pace, barely moving for much of the 24 hours after the lockdown warning on Tuesday, increases the danger of a long, destructive passage although late yesterday it appeared Port Hedland might escape the worst of the violence.

The Meteorology Bureau said Rusty was likely to result in an extended period of destructive winds and rainfall far heavier than normal cyclones.


Already locked down for more than a day, residents were warned they might have to remain indoors until tomorrow.

Late yesterday afternoon Rusty was estimated to be 125km northeast of Port Hedland and 190km north of Marble Bar, to the southeast, moving at about 5km/h.

The Pilbara coast was being hammered by gales that were expected to reach Marble Bar overnight, with destructive winds of more than 125km/h. The Meteorology Bureau warned that even stronger winds, reaching more than 165km/h, were likely to hit the Pardoo and De Grey regions, about 75km east of Port Hedland.

Flooding is a real threat.

Within a three-day period Rusty is predicted to dump the equivalent of Perth's winter rainfall on the region, with 600mm expected to fall in just 24 hours.

The bureau said major flooding was likely in the De Grey catchment, possibly extending through the nearby Fortesque catchment and along coastal streams.


It also warned of very dangerous storm tides extending well beyond normal high tide marks, and damaging waves along much of the coast.

The Western Australian Department of Fire and Emergency Services said lives and houses could be at risk from rising rivers in Marble Bar, Nullagine and De Grey Station.

More than 300 people were evacuated to emergency centres in Port Hedland, and schools were closed across the region.

Charter aircraft joined the evacuation of workers from major mines and drilling rigs as big miners Fortesque Metals and Atlas Iron shut down operations in one of Australia's most important resource regions.

Iron ore exports from the Pilbara exceed A$50 billion ($62 billion) a year, with new projects under way. The region also has vast oil and gas operations.

Rusty has shut down mines and closed Port Hedland, the largest bulk minerals export port in the world. Last year it handled almost 250 million tonnes of bulk cargo, mostly iron ore.


The nearby ports of Dampier and Cape Lambert have also closed.

- With AAP