A severe thunderstorm warning has been issued for parts of Perth, Mandurah and the South West.
Thunderstorms likely to produce damaging winds and heavy rainfall is expected over the coming hours.
Locations which may be affected include Bunbury, Busselton, Mandurah, Manjimup, Margaret River and Perth.
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 there is flooding, create your own sandbags by using pillow cases filled with sand and place them around doorways to protect your home.
* If boating, swimming or surfing leave the water.
* Do not drive into water of unknown depth and current.
* Slow down and turn your headlights on.
* Be alert and watch for hazards on the road such as fallen power lines and loose debris.
* If it is raining heavily and you cannot see, pull over and park with your hazard lights on until the rain clears.