The biggest storm front of the year is forecast to hit Mandurah and the South West on Sunday night.
The worst of the weather, including severe winds, is expected to hit Mandurah at about midnight and could continue until 5am.
The Bureau of Meteorology is predicting wind gusts of up to 125km/h while up to 25mm of rain is forecast to fall in some areas.
Department of Fire and Emergency Services metro district officer Chris Kin-Maung has told The West Australian, state emergency services and volunteers were on “heightened alert”.
“Even though householders may have been unscathed over the last couple of days, now is the time to prepare.
“If it is safe to do so, take action now.
"Prepare around the home, tidy up loose objects in the garden, secure trampolines, garden furniture and play equipment."
A flood watch has been issued for the South West and Lower West districts.
Locations that may be impacted include include Mandurah, Perth, Albany, Bunbury, Esperance, Katanning, Manjimup, Margaret River, Merredin, Moora, Mount Barker, Narrogin and Northam.
Warning out for severe winds over SW WA, see https://t.co/NikaX4QRKr. Windy conditions persist throughout Monday. #Perthweather #WAweather pic.twitter.com/W5YfOxKn0A
— BOM WA (@BOM_WA) August 13, 2017
Mandurah Crab Fest boasts huge range of free, family friendly entertainment
Fuel prices surge in Perth, Mandurah
Teen boys charged over Mandurah burglaries
Tragic update in search for missing man Robert Snyder
Premier Roger Cook to leave Kwinana electorate, move to Perth
Mandurah Marine Rescue's new vessel named in memory of nun who survived 1959 boating accident
Teen dies in motorbike crash at Waroona Dam
Shark alert issued after whale carcass reported at Preston Beach
Kwinana businesses to refuse serving students during school hours