Source: Bureau of Meteorology

For people in parts of Greater Perth area.

Issued at 9:20 am Wednesday, 13 September 2023.

The Bureau of Meteorology warns that, at 9:20 am, very dangerous thunderstorms were detected on the weather radar near Fremantle and Henderson.

These thunderstorms are moving towards the southeast.

Very dangerous thunderstorms are forecast to affect Armadale, Anketell, Byford, Gosnells, Jandakot, Jarrahdale and Roleystone by 9:50 am.
Other severe thunderstorms were detected on the weather radar near Parmelia, The Spectacles and Leda.

They are forecast to affect Mardella, Serpentine and Wellard by 9:50 am and North Bannister by 10:20 am.

Damaging, locally destructive winds are likely.

A 128 km/h wind gust at Rottnest Island was recently recorded with these storms.

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.