Severe Tropical Cyclone Ilsa has intensified into a category five system, with wind gusts of up to 315 kilometres per hour expected to lash the coast when it makes landfall tonight.
Ilsa was 290 kilometres north of Port Hedland at 9:00am this morning, moving south-southwest at 15 kph, with sustained winds near its centre of 165 kph and wind gusts to 230 kph.
It is now expected to cross the coast as a category five system.
Cyclone warnings are in place along more than 700km of coastline between an area south of Broome to Whim Creek, with alerts also extending hundreds of kilometres inland into the Eastern Pilbara and beyond.
The Bureau of Meteorology (BOM) said the most destructive winds would likely be felt between Bidyadanga and De Grey, where the cyclone was predicted to make landfall later tonight or early tomorrow morning as a "high-end" category-four system, most likely between Pardoo Roadhouse and Wallal Downs.
Cyclone Ilsa is expected to maintain a degree of structure and strength after making landfall, with damaging winds anticipated in Marble Bar and Telfer from this afternoon.
BOM meteorologist Jessica Lingard said strong winds and heavy rain would be felt far inland.
"The system is heading towards the coastline now so we are going to see conditions starting to deteriorate with some of those stronger gusts starting to be felt as early as later this morning," she said.
"We are seeing those seas and waves starting to be picked up, with seas and swells exceeding eight metres.
"It is going to be a very dangerous sort of day to be out on the coast.
"You can see on the latest tropical cyclone forecast map … that the 'confidence cone', that little greyed out area around the central track forecast, is quite skinny at the moment, indicating that we do have fairly high confidence on the forecast track of this system."
Final preparations for state's largest remote community
At Bidyadanga, 180km south-west of Broome, between 600 and 700 people are expected to shelter through the worst of the cyclone.
"We're just finalising a few things right now — checking on any potential rubbish or anything that could fly around," Bidyadanga chief executive Tania Baxter said.
"We're as confident as we can be, knowing that we have back-up.
"I feel like we've got good support, we just have to wait it out now."
Fresh supplies were trucked in from Broome yesterday, giving the community around seven days of food and fuel.
Ms Baxter said maintaining the community's power supply would be critical over the coming days.
"Without power, we haven't got water and possibly even communications," she said.
"So if we can maintain power supply then we'll be fine, we'll manage everything else that comes with it and any damage that comes."
Vulnerable locals evacuated
Longtime resident Frankie Shovellor said he was relieved some of the community's more medically vulnerable locals had been evacuated to Broome.
"It's a bit scary here, just knowing it's going to be a big one," he said.
"I think everyone's going to be prepared for the wind and rain, but it'll still be a bit scary for the young and old living in the community."
Three hours down the highway at Pardoo Station — the opposite side of Ilsa's predicted track — staff have spent the past two days making their final preparations.
Guests from the station's caravan park were moved on early, with remaining staff, contractors and neighbouring station owners working to secure the site.
"We're one day away and we're bracing for impact," Pardoo Beef strategic partnerships director Monica Chetty said.
"But we're prepared — as prepared as we'll ever be."
Around 20 remaining staff were due to relocate to Port Hedland yesterday, to shelter while the cyclone passed through.
'Do the right thing'
Julie Arif has lived in Port Hedland for 60 years and said people should take the warnings seriously.
"For me anything above a category three is cause for concern," she said.
"My husband and I have made our house and home as safe as we possibly can."
Ms Arif, who also manages the local visitors centre, said given the mining town's transient nature, this would be many people's first experience with a cyclone.
"Some are a little bit worried about what might happen and are reaching out via Facebook as to what can I do and things like that, and so everyone helps everyone else out."
She said a cyclone impacting at night can be frightening.
"Do the right thing and stay indoors. Don't do anything silly," Ms Arif said.
"Don't go having cyclone parties or anything like that because you do need to be aware and alert if something happens to your house and you have to evacuate — you don't want to be inebriated.
"This is a good opportunity to be enjoy your family — and in close quarters!"
Ms Arif said Tropical Cyclone Joan in 1975 and Tropical Cyclone George in 2007 were the worst she had experienced in Port Hedland.
Both impacted the region as category five cyclones.
Power, water, communications key
While the Department of Fire and Emergency Services (DFES) has worked to ensure adequate supplies to a number of remote communities, utility companies are putting lessons learned during this year's catastrophic Kimberley flooding into play.
Horizon Power community manager Michelle South said extra fuel had been dispatched to multiple communities.
"We're really focused on making sure the network is in good shape, and we're well prepared to respond to any potential impacts," Ms South said.
"We've actually undertaken a review recently in response to the Kimberley floods and basically identified exactly what we need in terms of fuel supplies to make sure we're well prepared."
Water Corporation north west manager Sharon Broad urged residents in impacted areas to stock up on emergency supplies of fresh water.
"You may have low water pressure or no water, due to damage in our infrastructure or power outages affecting our equipment," she said.
"Filling containers, buckets or sinks, we recommend that people require around 20 litres per day for drinking, washing and cooking."
Telstra regional general manager Boyd Brown said the telco had been inspecting transmitter sites and making contingency plans across the Kimberley and Pilbara.
"Like most major infrastructure, our base stations and telephone exchanges are reliant on mains power, but we do have temporary backups in place for short term outages," he said.
"If there is an extended outage, we will look to bring in temporary portable generators at impacted sites to help bring back connectivity."
The BOM said Cyclone Ilsa was expected to weaken below tropical cyclone strength overnight on Friday as it moved east into southern parts of the Northern Territory.
Great Northern Highway closed
The main artery linking Broome and Port Hedland — Great Northern Highway — has been closed to all traffic.
A 560 km stretch has shut between Pippingarra Rd at the Turner River bridge crossing to the turn-off to Broome at the Roebuck Roadhouse.
Marble Bar Road and Ripon Hills Road have also been closed.
People have also begun arriving at evacuation centres in Marble Bar, Nullagine and Newman.
Another evacuation centre has opened at the JD Hardie Centre in South Hedland.
Pilbara DFES Superintendent Peter McCarthy said he believed the entire coastal region had been cleared of people camping and caravanning.
"They've all emptied out now under yellow and you'll find caravan parks in Hedland now will be moving people on. So we could see people moving down towards Karratha later this afternoon," he said.
