Millions are bracing for impact as a powerful storm system brings destructive winds.
The weather event, seen only once every five years, could bring wind gusts of up to 125km/h to Perth and communities along Western Australia's coast.
"This situation definitely doesn't happen every year and the wind is going to be the worst hazard," Bureau of Meteorology duty forecaster Luke Huntington told AAP.
Residents have been urged to close their curtains and remain inside away from windows as the low-pressure system approaches the state's southwest on Sunday morning.
"People should definitely tie down loose items like outdoor furniture and trampolines," Mr Huntington said.
"When those strong winds are coming through, make sure you stay inside and just stay off the roads, in case of fallen power lines or trees."
