After an "eerie" feeling bracing for a dangerous tropical cyclone, a regional hub has been spared the worst from the category-five storm.

Residents in Port Hedland had braced for serious damage as Tropical Cyclone Zelia made landfall, prompting authorities to put the Australian Defence Force on standby to assist.

Zelia hit the coast hours earlier than expected on Friday, unleashing 290km/h winds and triggering flash flooding.

That sparked memories of Cyclone Ilsa's deadly impact in 2023 which claimed eight lives.

But Zelia was quickly downgraded to a category four as it moved east of Port Hedland, still producing winds up to 250km/h, heavy rainfall and a "dangerous" storm surge.

Residents from Pardoo Roadhouse to Whim Creek and inland to west of Marble Bar were told to take shelter, with authorities warning it was too late to leave.

Zelia was initially set to hit the region late on Friday with shops, schools, roads and ports in WA's northwest closed in preparation and locals warned to take shelter.

But authorities confirmed Zelia had crossed hours earlier than predicted, bringing damaging winds, flooding and heavy rainfall.

"We've got a whole raft of resources ready to go should they be required ... for really catastrophic damage," WA Fire and Emergency Services Commissioner Darren Klemm said.

WA Premier Roger Cook earlier confirmed the Australian Defence Force was on standby to assist, with Zelia triggering destructive wind gusts of up to 290km/h, intense rainfall and flash flooding.

Port Hedland, which had been fearing the worst after the category five Cyclone Ilsa system struck in 2023, claiming eight lives, was expected to dodge a bullet.

"Port Hedland is not expected to be impacted by the very destructive winds," the Bureau of Meteorology's Matt Collopy said.

Port Hedland Deputy Mayor Ash Christensen said there had been an "eerie sort of feeling" around the community as residents waited for the cyclone to strike.

"We put a brave face on but I think everyone, deep down inside are a little bit worried about this one," he said.

Zelia rapidly intensified as it zeroed in on Australia's coast, developing from a category three to a five in 24 hours - progress experts claimed was "highly unusual".

Evacuation centres have been set up at Karratha and South Hedland, with major highways near Port Hedland and regional airports closed.

Prior to the storm, Port Hedland local Tracey Heimberger was keeping her fingers crossed her house "holds together" after opting to sit out the storm with her partner at home. 

"I'm a bit scared actually. It's going to be a heck of a storm," she said. 

"It's started getting really gusty already. Hopefully our house holds together."

"We've done all preparations we can. We've even put our passports in zip-lock bags."

Ms Heimberger was also concerned for the safety of locals, saying many homes in the town weren't designed to withstand a category five cyclone.

"Especially people living in our outlying communities. I really hope they've got to town."

The Bureau of Meteorology said wind gusts of 120km/h had been recorded recorded near Port Hedland earlier with rainfall totals slowly increasing. 

In the last 24 hours, Wallal Downs recorded 90mm after downpours of several 100mm fell in a matter of days.

A "shelter indoors now" alert was issued for Pardoo Roadhouse to Whim Creek and west to Marble Bar.

"It is too late to leave," the Bureau of Meteorology said.

Other towns like Karratha, Dampier, Tom Price, and Eighty Mile Beach have been warned to prepare to take shelter.

Shops, schools, roads, airports and ports in the state's northwest have closed in preparation for the dangerous system.

Winds up to 150km/h are expected to impact coastal areas but 300km/h gusts are forecast for the region the cyclone was expected to cross, east of Port Hedland.

"These are extremely destructive winds. Winds so powerful it can take out trees, power lines and entire houses and really destroy anything in its path," meteorologist Angus Hines said.

Rainfall up to 500mm was expected to inundate the region with a significant storm tide also forecast that may lead to coastal road and home flooding.

Flash flooding has already begun to inundate roads with reports a road train was washed off a Marble Bar bridge.

Experts are extremely concerned about the cyclone's impact on northwest WA, particularly iron ore hub Port Hedland.

"Even buildings and infrastructure built to the highest cyclone rating standards will receive some structural damage from the predicted extreme winds in the core of the cyclone," Professor Steven Turton from Central Queensland University said.

Prof Turton said offshore sea temperatures were feeding the cyclone which may cause significant damage to the remote area.

"Despite the small size of the system, its slow forward motion will mean prolonged extreme winds and intense rainfall around the core as it approaches and crosses the coastline," he said.

Evacuation centres have been set up at Karratha and South Hedland, with major highways near Port Hedland and regional airports closed.

Meanwhile, north Queensland was recovering from its own flooding disaster with power restored to 30,000 homes after a fortnight of record falls that caused two deaths and hundreds of evacuations.

The federal government has announced $84.8 million to 18 local government areas in northern and western Queensland to undertake major infrastructure and flood mitigation upgrades.