A severe thunderstorm warning has been issued for Mandurah, Rockingham and Perth.
Thunderstorms will likely produce damaging winds over the next several hours.
Rockingham (Garden Island) recorded a wind gust of 98km/h just after 5.30am on Wednesday.
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.
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