Cyclone Errol grows to category 4 storm as isolated communities brace for wild weather

A cyclone off Western Australia's northern coast has intensified into a category 4 system overnight as it heads towards isolated communities.

Severe Tropical Cyclone Errol was about 500km north-west of Broome early today.

It has been moving south, but over the coming hours is forecast turn south-east and track towards the west Kimberley coast.

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The Bureau of Meteorology is warning if the powerful storm moves faster than forecast, it could bring destructive wind gusts of up to 130km/h between Cockatoo Island and Beagle Bay late tomorrow.

Damaging wind could also extend further south to Broome, if the storm alters slightly south of its current forecast, the bureau says.

Senior meteorologist Angus Hines says Errol is expected to start weakening quickly today, decreasing in strength to category 2 before it continues to lose strength through the weekend.

But communities are likely to feel its impact through tomorrow.

"From Thursday, Tropical Cyclone Errol could steer south-eastwards back towards the coast," Hines said.

"While it is forecast to weaken, while doing so, it may bring impacts such as heavy rain, thunderstorms and damaging wind to parts of the Kimberley and Eastern Pilbara over the weekend."

The weather system is forecast to arrive around the northern tip of the Dampier Peninsula early on Saturday morning as a category one storm, which is capable of producing wind gusts up to 125km/h.

The bureau has issued a cyclone watch has been issued for the Kimberley coast stretching from Kuri Bay to Broome.

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