The clean-up has continued in the Perth suburbs of Morley and Dianella after yesterday's tornado.

The State Emergency Service (SES) it received a further 15 calls for assistance today after a tornado ripped through Morley and Dianella yesterday.

About 120 people in total called for help, after winds of up to 125 kilometres an hour caused extensive damage to homes and businesses.

The SES says most of the fallen trees and debris from damaged homes has been cleared off the roads.

Allen Gale from Fire and Emergency Services (FESA) says people need to prepare their homes for the winter months.

"It certainly is the time to put away that outdoor furniture, that garden type furniture, at least weigh things down that are likely to become airborne," he said.

"And make sure your gutters are clear, rain damage, rain overflowing from gutters is usually the biggest cause of calls to the SES and a lot of it is avoidable."

Mr Gale says the clean up effort has been tremendous.

The tornado uprooted trees, brought down power lines, and lifted roofs from buildings in the suburbs of Dianella and Morley.

The tornado lasted only about 10 minutes, but packed winds of up to 125 kilometres per hour and caused damage worth millions of dollars.

Morley video store manager Michael Williams says it was an extraordinary experience.

"It was really windy. I looked out the windows and there was just stuff flying in the sky," he said.

"Then we were just standing at the window having a look and the roof just started going boom, boom, boom with the wind, so we just ran to the back of the store and as we were running the windows just smashed in."

Emergency services officers walk through a video store destroyed by a tornado which swept through Perth's northern suburbs. ( ABC TV )

Electrician James Stevenson was in the Galleria Shopping Centre car park in Morley when the storm hit.

"It went across the top of the shopping centre, ripping all the shade sails off, smashing them on to cars and there was power lines down in the street with wires across the road," he said.

Another witness, Shelby Ginger, had just arrived to pick her children up from school.

"So we got out of the car to walk towards the school and all of a sudden it just bared down and started," she said.

"Everything was flying towards us so we jumped under a tree and saw it go down the road ripping trees up - just scary."

Powerful gusts of wind and rain also lashed the town of York from about 12:30pm (AWST) but there were no reports of injuries or damage to homes.

Neil Bennett from the Bureau of Meteorology says the tornado struck without warning.

"The unfortunate nature of these things; they live fast and die young," he said.

"We don't really have the ability to predict exactly where they're going to occur.

"We can predict an area where we think they may occur but the actual pinpointing of them is next to impossible.

"They're probably on the ground for no more than 10 minutes."