Resident in the Peel region and across the state are being urged to prepare for the possibility of "significant bushfires" this weekend, with high temperatures and strong winds likely to create dangerous conditions in the southern half of the state.
If temperatures in Perth reach the predicted maximum on Saturday, it will be the earliest occurrence of a 40-degree day in November since records began.
Department of Fire and Emergency Services (DFES) deputy commissioner Craig Waters urged the public to be aware of their surroundings and act immediately if they see smoke or flames.
"This weekend's conditions mean the smallest of fires can escalate quickly and become unstoppable, so you need to take steps now to ensure you are prepared," he said.
"Visit firechat.wa.gov.au and have a five-minute fire chat with your family about what you will do if a bushfire threatens your area.
"You need to know what your triggers are to leave, where you will go and how you will get there. Knowing these three things will give you the greatest chance of survival should a bushfire occur."
Waters said firefighters are ready to respond but safety was everyone's responsibility.
"There will never be as many fire trucks as there are homes," he said.
"You cannot wait for a text or a knock on the door - you need to take action and stay up-to-date."
Bureau of Meteorology acting state manager James Ashley said a combination of high temperatures, strong winds and dry conditions would lead to severe-to-extreme fire danger ratings for parts of southern WA.
"A high-pressure system moving into the Bight will direct hot and dry north-easterly winds over the west coast on Saturday, causing temperatures to increase to 40 in some places, including Perth," Mr Ashley said.
"The hot air will move eastwards on Sunday, and the eastern Wheatbelt, Goldfields and South East Coastal districts are likely to experience temperatures in the high 30's.
"If Perth reaches its predicted top of 40°C on Saturday, it will be only the third time it has reached 40°C in November since temperature records began in Perth in 1897."
Mandurah is currently slated to peak at 39 degrees on Saturday.
For more information on how to prepare and respond to bushfires visit emergency.wa.gov.au or call DFES on 13 33 37.
Stay up to date with weather information by monitoring the latest forecasts and warnings at bom.gov.au/wa