Tropical Cyclone Sean forms off WA coast amid wild weather warnings

Tropical Cyclone Sean was declared on Sunday north of the Pilbara Coast in Western Australia, with the category one storm expected to strengthen, but remain off the coast.

The cyclone has halted iron ore exports across much of the Pilbara, where about 43 per cent of the global iron ore trade and 7.5 per cent of the global LNG trade is sent from.

A storm tide is expected between Port Hedland and Exmouth as the cyclone progresses.

A cyclone emergency warning was issued for Barrow Island on Sunday afternoon, with residents warned there was a risk to life and property.

People were told to shelter indoors and stay in the strongest, safest part of the building.

A cyclone “watch and act” alert was issued from Mardie to Ningaloo, not including Mardie with destructive winds expected on Sunday afternoon and evening.

“With those very strong gale force winds and a bit of swell around, it’s going to be very rough seas,” Bureau of Meteorology forecaster Luke Huntington said.

The Bureau of Meteorology said damaging wind gusts and heavy rain were possible in Port Hedland, Karratha and Dampier.

The Port of Port Hedland has been closed with all boats to leave tonight.

Meanwhile, the south-west is preparing for extreme heatwave conditions.

Temperatures are forecast to climb as high as 42 degrees next week.

AAP with Nine News Perth