Residents are being urged to prepare now for severe weather coming on Tuesday morning.
A cold front bringing windy conditions, heavy rainfall and thunderstorms is set to hit the coast from Jurien Bay down to Walpole including Perth, Mandurah and Rockingham.
Residents can expect damaging wind gusts of 100km/h and between 40mmm and 60mm of rain.
Conditions are expected to ease on Tuesday afternoon.
Locals are being advised to pack away, secure or tie down outdoor furniture, trampolines and other loose items around the home.
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