Severe Tropical Cyclone Hayley has been downgraded to a category two system as it moves eastwards across Western Australia's Kimberley coast.

The eye of the cyclone crossed the tip of the Dampier Peninsula coastline, north of Broome, around 5pm (WST) on Tuesday evening.

The Bureau of Meteorology (BOM) says the storm is gradually weakening, with sustained winds of 110 kilometres per hour near the cyclone's centre, with wind gusts of up to 155kph.

The storm is currently 80km north west of the town of Derby.

A warning zone is in place north of Beagle Bay to south of Kuri Bay, while warnings have been cancelled for parts of the Dampier Peninsula near and south of Beagle Bay, as well as Derby and Kuri Bay.

Heavy rainfall is also expected, with the possibility of flash flooding in the next 24 hours.

The Broome Cape Leveque Road closed as Tropical Cyclone Hayley neared. (ABC News: Andrew Seabourne)

Cyclone Hayley is expected to continue to weaken in intensity as it heads east over land and could drop to tropical low status as early as Wednesday morning.

BOM WA state manager James Ashley said the system had sped up from 12km/h to 23km/h in the final hours before crossing the coast.

"You can clearly see on the radar it has crossed south of the community of Djarindjin," he said.

"I imagine that area is getting absolutely pummelled by wind and rain."

Debris warnings

Department of Fire and Emergency Services (DFES) acting Kimberley superintendent Todd Pender said loose debris was a key concern for residents in the emergency warning zone.

"As those gale force winds intensify to damaging and then also to destructive, they have the propensity to pick up the debris and fly it around the community," he said. 

Emergency service crews were bolstered ahead of the cyclone. (ABC Kimberley: Rachel Jackson)

"There is a very high potential for damage. We are going to see structures damaged by this event, unfortunately."

Mr Pender said coastal communities could experience destructive winds.

"The category three circumstances, that environment, is probably going to last right up until it gets to the coast," he said.