A Mini-tornado has ripped through suburban Perth, ripping down powerlines and trees and leaving a trail of damage.

Several reports on Twitter described the storm as a "small tornado''. It is believed the destructive winds centred on Light Street, Dianella and Alexander Drive, and hit around midday WA time.

A real estate office and video store on Walter Road, Morley, has been damaged with the roof torn off and one wall collapsed.

Nobody was injured in the building collapse. Several cars may also have been damaged.

The Bureau of Meteorology confirmed that a "tornado'' was reported in the Tuart Hill/Morley/Dianella area just after midday.

At 12.45 pm the storm that produced this tornado was in the vicinity of Bickley and moving to the southeast.

Another tornado has been reported near York at around 12.30 pm.

The bureau also issued a severe thunderstorm warning for the area.

Thunderstorm warning

Warning: "For destructive winds and heavy rainfall in, near or between a line Jurien Bay to Beacon to Corrigin to Bunbury to Jurien Bay, including York, Mandurah and the Perth metropolitan area.

"A low pressure system to the southwest of Perth is producing showers and thunderstorms over the southwest of the State with isolated dangerous that could cause significant damage to homes and property. Showers and thunderstorms may also cause heavy rainfall that may cause flash flooding during this afternoon.''

The tornado has ripped powerlines and trees down on Morley Drive between Alexander Drive and Camboon and Wellington Roads.

Western Power crews are on site and are currently assessing the damage.

Approximately 5000 thousand customers have been blacked out and Western Power will be seeking to restore their power as soon as possible.

People are urged to stay away from any fallen power lines and report any damage to 13 13 51.

Trees have also been brought down along Alexander Drive.

Police and emergency services are on site directing traffic.

Drivers are strongly advised to avoid the area if possible.

Other roads in and around the Dianella/Morley area may also have debris or water over the road so drivers are asked to reduce their speed and exercise caution through the area.