Tropical Cyclone Narelle has strengthened to a category four system as it approaches the coast of northern Western Australia (WA), the Bureau of Meteorology of Australia warned on Friday.

The national weather agency says a cyclone warning continues for coastal areas of WA from Whim Creek to Coral Bay, including Karratha, Dampier, Onslow and Exmouth.

At 5:00 a.m. local time on Friday, category four Cyclone Narelle was estimated to be 535 kilometers north of Exmouth and 505 kilometers northwest of Karratha and moving southwest at 15 kilometers an hour, according to the Bureau of Meteorology.

Gales with gusts to 100km an hour are expected to develop in coastal areas between Whim Creek and Exmouth on Friday afternoon, then extend south to Coral Bay on Saturday morning, the Bureau said.

Residents on the Pilbara coast are being warned to prepare for possibly destructive wind gusts over 130 kilometers an hour overnight Saturday.

Mining companies in WA have already reacted to the cyclone warnings with iron ore ports at Cape Lambert and Dampier due to close, and Apache closing down the Stag and Van Gogh oil fields on Thursday, the Australian Associated Press (AAP) reported.

Chevron is preparing to evacuate its employees from Barrow Island. Endi