Western Australia is being battered by dangerous weather, with damaging winds and heavy rain lashing most of the state in a "rare event".
It is expected to be WA's wildest autumn weather in years, as the remnants of ex-tropical cyclone Mangga collide with a cold front and trough, whipping up gusts of about 100 km/h.
"This is a rare event for Western Australia, particularly due to the extent of the area affected and the possibility of multiple areas of dangerous weather," the Bureau of Meteorology said.
"A similar event to this one occurred in June 2012, which led to over 600 calls for assistance and over 170,000 homes losing power."
The Department of Fire and Emergency Services warns the "unusual weather" could cause significant damage to homes and make travel dangerous.
Strong winds are already raising dust through large parts of the Gascoyne and Central West areas, blanketing Geraldton.
A "take action now" alert is in place for most of the state, including Perth which is expected to get its strongest lashing on Sunday night.
Residents have been warned to unplug electrical appliances, avoid using landline phones if there is lightning, close curtains and blinds, and stay away from windows.
Anyone stuck outside should find safe shelter away from trees, powerlines, storm water drains and streams.
Motorists are warned to watch for hazards, such as debris, and to not drive into water of unknown depth and current.
Residents in coastal areas from as far north as Exmouth and south to Augusta are specifically warned of the potential of a dangerous storm tide.
Peak wave heights in excess of eight metres are predicted for the south west coast on Monday, causing significant beach erosion.
Winds are expected to ease across the Pilbara and Gascoyne regions overnight, and through the south-western part of the state during Monday.
Western Power says there are currently about 18,000 properties experiencing storm outages.
Regional towns most heavily impacted include Kalbarri, Port Denison, Dongara, Cape Burney, and Greenough.
Perth suburbs most affected by outages are Mount Helena, Gidgegannup, Bailup, Sawyers Valley, Bayswater, Bassendean, Ashfield and Wooroloo.
