Pinjarra and surrounding areas could be lashed with damaging winds today.
The Department of Fire and Emergency Services has urged residents to close curtains and blinds, and stay away from windows.
If outside, find safe shelter away from trees, power lines, streams and stormwater drains.
Conditions on the roads could also be affected, so slow down and ensure your lights are on.
DFES has said this is unusual weather that could cause damage to homes and make travel dangerous.
The alert also affects regions of Perth, Gingin, Harvey, Midland and Mundaring.
For more information visit emergency.wa.gov.au.
If your home is badly damaged call SES on 132 500.
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