Up to 100 vehicles were involved in multiple collisions on Highway 401 between London and Tilbury, according to Ontario Provincial Police.

Motorists are being warned to stay off the roads if possible as the hazardous system moves east through the Waterloo region into the greater Toronto area.

“Please, if you don’t have to be out, stay at home and wait for this system to go through. Let the plows and salt machines do their work. The best place is off the freeway,” OPP Sgt. Kerry Schmidt said in a video posted to Twitter at 12:18 p.m. Friday.

Highway 401 between London and Tilbury and Highway 402 between London and Sarnia were completely closed in both directions on Friday, with an Ontario provincial police officer describing the corridor as “one of the worst traffic scenes” he had ever seen.

Fortunately, police say there were no serious injuries in any of the multi-vehicle collisions along the corridor. Two people were taken to the hospital with non-life-threatening injuries.

At 1 p.m. Ontario provincial police said all roads were closed in neighboring Perth County, where a snow storm warning is in place and Environment Canada says up to 50cm of snow could fall from here Sunday morning. Major roads in nearby Huron County were also closed about an hour later.

Environment Canada is warning that the storm system that swept across Ontario and Quebec on Friday and is expected to last through Saturday could be a one-off event.

“We might only see one of these storms every five or 10 years,” said Environment Canada meteorologist Mitch Meredith. “I’ve seen few storms like this in the last 20 years.”

High winds, high levels of sluggishness and a possible flash freeze caused school cancellations in southern Ontario, including the Waterloo area, on Friday.

In Ayr, 2,458 homes and businesses lost power for several hours on Friday. At 4 p.m., around 1,000 people were still without power.

In Guelph, as of 4:00 p.m., 219 homes and businesses in the area around Woolwich Street and Speedvale Avenue were affected by a power outage.

According to Environment Canada, travel in the Waterloo area and southern Wellington County is “unsafe and not recommended”.

In northern counties of Wellington, Huron and Perth, the weather agency says “crippling snowstorm conditions” will make travel “at times impossible” with wind gusts of up to 90-100km/h.

CAA South Central Ontario (CAA SCO) says emergency calls and services will be prioritized for members in hazardous conditions during extremely high demand for services. Members who are safely waiting at home may be waiting longer than expected, according to the CAA.

Blowing snow creates dangerous conditions on a freeway in Kitchener on Friday, December 23, 2022. (Chris Thomson/CTV Kitchener)

In Stratford, a bus that got stuck on an icy hillside pulled several cars into the ditch to avoid the disabled vehicle.

“I was going down John Street and I wasn’t going very fast but the mobility bus was going down the road and I couldn’t stop so I came here instead of meeting it,” a driver told CTV News.

Another, scheduled to return to Woodstock, decided to leave work early.

“Bad roads, all bad,” he told CTV News. “A lot of slides, a lot of slides. You can’t see 100 meters in front of you.”

The storm upended vacation travel plans for thousands of people as airlines pre-emptively canceled flights and more disruption was expected.

Passengers wait for a bus after their GO train was canceled in Kitchener. (Chris Thomson/CTV Kitchener)

WestJet announced Thursday night that it was canceling flights at airports in Ontario, Quebec and British Columbia.

The cancellations apply to all flights scheduled to arrive and depart from Toronto Pearson International Airport from 9 a.m. Friday until the end of the day, the airline said. Other airports impacted by disruptions include Ottawa, London, Ontario, Waterloo, Ontario and Montreal.

With files from The Canadian Press

Blowing snow reduced visibility in downtown Kitchener on Friday, December 23 during a major winter storm. (Chris Thomson/CTV Kitchener)