A strong cold front will sweep over Mandurah, the South West and parts of the Great Southern on Tuesday afternoon.
Thunderstorms, showers and damaging winds of up to 100km/h will hit areas including Mandurah, Bunbury, Busselton, Manjimup, Margaret River, Harvey and Walpole from about 2pm and continue into Wednesday morning.
Damaging surf conditions are likely to cause significant beach erosion between Lancelin and Cape Leeuwin.
"This is typical weather for this time of the year but winds may cause damage to property and make road conditions hazardous," A Bureau of Meteorology spokesperson said.

The Department of Fire and Emergency Services advises that people should:
* If outside find safe shelter away from trees, power lines, storm water drains and streams.
* Close your curtains and blinds, and stay inside away from windows.
* Unplug electrical appliances and do not use land line telephones if there is lightning.
* If boating, swimming or surfing leave the water.
* Be alert and watch for hazards on the road such as fallen power lines and loose debris.
* Keep away from flooded drains, rivers, streams and waterways.
* Be careful of fallen trees, damaged buildings and debris.
* Be careful of fallen power lines. They are dangerous and should always be treated as live.
* Assess your home, car and property for damage.
* If damage has occurred take photos and contact your insurance company to organise permanent repairs.
* If your home or property has significant damage, like a badly damaged roof or flooding, call the SES on 132 500.
Peel Thunder cruise into 2026 WAFL grand final
Two teens cautioned, one charged over brutal Falcon attack
Nearly 100 new rentals to be built in Mandurah
Blue swimmer crabs off limits during season closure
Fire crews on scene of Meadow Springs house fire
Perth's southern suburbs declared One Nation's 'heartland' after Secret Harbour by-election victory
Construction contract awarded for Kwinana Freeway upgrade
Port Kennedy humpback whale buried at landfill facility
Secret Harbour by-election: Where to vote on August 29