The Bureau of Meteorology has warned Perth and south-west residents the "most significant cold front" of the year is expected to hit on Sunday evening.
The Sunday cold front is expected to be one of three forecast for WA over the weekend, with the first predicted to hit the south-west coast at around 8pm on Friday evening.
The first cold front will roll through to Perth at around midnight, bringing with it wild winds in excess of 100km/h.
The second front is forecast to bring severe weather on Saturday evening, although it is not expected to be as strong as Friday evening's severe weather.
Bureau of Meteorology spokesperson Neil Bennett said Perth and residents in WA's south-west should prepare for the potentially severe weather.
"On Sunday evening the Bureau is predicting the most significant cold front of the season so far, with widespread damaging winds and gusts in excess of 125km/h expected for the Perth area and southwards," he said.
"This cold front is expected to be windier than a typical front, and is likely to produce the kind of weather that is only seen during winter around twice a season."
The Bureau has forecast wind gusts in excess of 100km/h winds for the Perth area throughout the weekend.
Residents have also been told to be conscious of flash flooding, as Flood Watch alerts have been issued for the south west region of WA.
People in Mandurah, Serpentine, the Murray River basin catchment and the Harvey River catchment have been warned tp prepare for possible minor flooding expected this evening and over the coming days.
Emergency Services said some roads may be closed due to flooding, and said their officials were monitoring the situation.
"Recent rainfall over the past week has caused river rises in the lower west district, and further rainfall associated with the passage of the cold fronts this weekend is expected to result in renewed river rises and areas of flooding, mainly in the southern half of the lower west district," a spokesperson for the Department of Fire and Emergency Services said.
Residents have been told to:
- Prepare to relocate equipment and livestock early so they are not caught in floodwaters.
- Prepare an emergency kit including enough canned food and water to last for four days, as well as clothing, important documents and medication.
- Fill your vehicle's fuel tank.
- Watch for changes in water levels so you are ready if you need to evacuate
- Never walk, swim or play in floodwaters, as they are dangerous.
- Stay out of rivers, this includes no swimming or kayaking.
- Do not park or camp adjacent to rivers.
The August average is typically around 132.9mm, and Perth has already recorded 87.8mm just 11 days into August.
This weekend's forecast could see Perth rain gauges creep closer to exceeding the monthly average.
A series of cold fronts will move over SW WA this weekend. Gusty winds, showers and storms possible. Latest info at https://t.co/FtoaxBq1xe pic.twitter.com/g2cgY956TH
— BOM WA (@BOM_WA) August 10, 2017