More than 3,500 homes and businesses in Port Hedland are without power after Tropical Cyclone Heidi swept through the Pilbara town this morning.
The system has been downgraded to category one and is losing power as it moves inland through the north west of Western Australia.
While residents are reporting the worst of the cyclone has now passed Port Hedland and South Hedland, a red alert is still current for Pardoo to Whim Creek, where authorities are urging residents to remain indoors.
An all clear is expected to be issued this afternoon.
The ABC's Elise Batchelor lives in Port Hedland and says Heidi packed winds of up to 150km per hour in the height of the storm.
"We've got a smashed pot or two; I've got chimes going mad and in fact the man hole in our house up in the ceiling has been lifted off by the pressure of the wind," she said.
Ms Batchelor says residents are starting to go stir crazy as they are instructed to remain in their homes while emergency crews survey the damage.
Horizon Power cannot dispatch crews to start restoring power until an official all clear is issued.
Despite the storm passing, the Fire and Emergency Services district manager for the East Pilbara Jim Cahill says residents must stay indoors.
"If they see emergency crews on the street it doesn't mean it is safe for them to go out," he said.
"It's just for emergency crews only and the all clear precaution will be issued as soon as possible."
FESA now says residents in low lying parts of Port Hedland are no longer under threat of a storm surge.
Brad Murphy lives in South Hedland and says his street has been completely flooded.
"Out the front of my house the water is actually over the road, so I'd say 250 millimetres [of rain]," he said.
Earlier Tom, who lives near Port Hedland, said the winds were fierce and his house was flooding.
"We are getting smashed now, mate," he told ABC Radio just before the cyclone made landfall.
"We are getting smashed now. There is full horizontal rain and very high winds."
The heaviest rainfall is expected to the east and south of the system, and a flood alert has been issued for surrounding areas of the Pilbara.
About 45 people took refuge at a relocation centre in South Hedland overnight.
Australia's largest bulk export port at Port Hedland has been shut down as the cyclone nears.
The port's Steed Farrell says bulk ore carriers and other ships have been sent to safer waters.
"The last thing we want is for those vessels to break their mooring and run aground or cause damage, so it's always much safer for vessels and port to clear the vessels to safer water outside the cyclone area," he said.
Dampier Port has sent the big ships out to safer waters.
Rio Tinto and Fortescue Metals have stopped loading ships.
Oil and gas producers Woodside Petroleum and Santos say they have stopped production at some of their oilfields off the coast as the cyclone approaches.
Meanwhile, the Karijini and Millstream Chichester national parks remain shut after the rain caused flash flooding and inundation of roads and campsites in the parks.
Duty forecaster Darryl Vink says WA should be prepared for a number of cyclones this season.
"Potentially, we normally get four to five cyclones per season; we forecast slightly above that this year so we could expect another four to five, I guess," he said.
© ABC 2012
18:16 EST Heavy rain has stranded about 40 people at William Creek in the South Australian outback due to flooded roads and low cloud has grounded aircraft.