Intense storms are lashing the western coast of Australia with an unusually deep low pressure system packing powerful winds and heavy rain.

The extreme weather eventbrought wind gusts of up to 125 km/h to Perth and communities along Western Australia’s coast on Sunday afternoon.

Images of widespread destruction have flooded social media, including one showing a shed seemingly tossed into a swimming pool in Mandurah in the state’s south-west.

WA’s Department of Fire and Emergency Services issued an alert on Sunday afternoon, warning residents to “act now and stay safe, with damaging to destructive winds expected this afternoon and evening”.

“Rarely experienced winds may bring down trees, branches and powerlines and loose items or debris may become airborne.”

There were about 130 power outages recorded in multiple parts of Perth and its surrounds, with 14,600 customers affected statewide, according to Western Power.

Wind gusts of 117 m/h were recorded at Cape Leeuwin in the morning, while 104km/h gusts were marked at Cape Naturaliste.

The deep low pressure system brought high tides and eight-metre waves while flooding in Perth’s CBD stranded cars and submerged walkways.

Residents had been urged to close their curtains and remain inside away from windows as the system approached the state’s southwest in the morning.

“People should definitely tie down loose items like outdoor furniture and trampolines,” Bureau of Meteorology duty forecaster Luke Huntington told AAP.

“When those strong winds are coming through, make sure you stay inside and just stay off the roads, in case of fallen power lines or trees.”

Football fans attending the West Coast Eagles v Essendon match at Optus Stadium were also been urged to plan ahead.

“This situation definitely doesn’t happen every year and the wind is going to be the worst hazard,” Huntington said.

A major police search earlier wrapped up when an 11-year-old autistic boy was found safe after going missing overnight in Perth’s western suburbs during the wild weather.

The boy, who is nonverbal, had been missing for almost eight hours, prompting a large-scale search involving police and State Emergency Service volunteers on foot and horseback.

Several WA towns recorded heavy rain as the weather system moved through, with Ludlow, about 200km south of Perth, receiving 43mm in two hours on Saturday night.

The cold front and low-pressure systems are expected to sweep across western parts of South Australia during Monday, bringing rain and wind gusts of up to 100km/h before moving across the Adelaide region later in the day.

Severe weather warnings have been issued for SA’s coastal regions, the Mid North and the south-east.