After a night of constant downpour Emergency WA said residents in parts of the Perth Metropolitan and South West should brace and take action with more severe weather on the way.
Overnight Mandurah recorded 79 mm of rainfall, well and truly over the 9.5 mm average for the month of January.
The highest recorded rainfall for January in Mandurah was taken in 1982 when 224.2 ml of rain fell.
This weather is not unusual for this time of year, but could damage homes and make travel dangerous.
Earlier this morning the Bureau of Meteorology confirmed on Monday a low pressure system was off the coast to the west of Jurien Bay and by tonight it's predicted to have moved off the coast to the west of Bunbury.
The low pressure system is expected to bring heavy rainfall that may lead to flash flooding over the southern lower west district, far southwest Central Wheat Belt, western Great Southern and northern parts of the South West district.
This includes southern suburbs of the Perth Metropolitan area.
Several sites in the Perth metropolitan area have received over 120 millimetres of rain since Monday morning.
• If outside find safe shelter away from trees, powerlines, storm water drains and streams.
• Close your curtains and blinds, and stay inside away from windows.
• Unplug electrical appliances and avoid using landline telephones if there is lightning.
• If there is flooding, create your own sandbags by using pillow cases filled with sand and place them around doorways to protect your home.
• If boating, swimming or surfing leave the water.
IF DRIVING:
• Do not drive into water of unknown depth and current.
• Slow down, turn your lights on and keep a safe distance from other drivers.
• Be alert and watch for hazards on the road such as fallen powerlines and loose debris.
• If it is raining heavily and you cannot see, pull over and park with your hazard lights on until the rain clears.
• Take care in areas that have been flooded and be careful driving on gravel roads as surfaces will be slippery and muddy, and vehicles could become bogged.
People are being urged to do what they can to help themselves, if it is safe to do so, before calling the SES for assistance.
You can keep up to date with weather updates by visiting the Emergency WA website www.emergency.wa.gov.au
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