A major winter storm bearing down on Ontario and Quebec cancelled flights, closed schools and threatened widespread power outages Friday, with an Environment Canada meteorologist warning of a possible once-in-a-decade weather event.
Environment Canada predicted strong winds, heavy snowfall and possible flash freezing, issuing winter storm warnings for most of Ontario and Quebec.
"We may only see one of these storms every five or 10 years," said Environment Canada meteorologist Mitch Meredith. "I've only seen a couple of storms like this in the last 20 years."
In parts of southern Ontario, rain followed by plummeting temperatures could result in flash-freezing conditions later Friday morning, while high winds and blizzard conditions are forecast for some areas.
Environment Canada forecast winds up to 100 kilometres an hour in certain regions of the province – higher in some areas around Lake Ontario such as Niagara and Kingston – and warned of possible widespread utility outages.
"The problem with that is the temperatures (are) going down way below zero right when we're getting power outages. So, this is a dangerous situation for people," Meredith said.
In Quebec, many regions are expected to receive a mix of heavy snow, rain and strong winds, while some areas could see freezing rain.
The incoming storm upended holiday travel plans for thousands of people as airlines pre-emptively cancelled flights, with more disruptions expected.
WestJet announced late Thursday that it was cancelling flights at airports in Ontario, Quebec and British Columbia.
The cancellations apply to all flights scheduled to arrive and depart Toronto's Pearson International Airport beginning Friday at 9 a.m. until the end of the day, the airline said. Other airports affected by the service disruptions include those in Ottawa, London, Ont., Waterloo, Ont., and Montreal.
Air Canada said Friday that it had cancelled "a number of flights" in Ottawa, Montreal and Toronto, including all its flights out of Toronto's downtown island airport, citing the storm, reduced airport capacity and operational constraints.
The Toronto Transit Commission took out of service 41 bus stops in hilly areas difficult to navigate in snowy and icy conditions. GO Transit, which serves the Greater Toronto and Hamilton Area, cancelled express trains and reduced train service during peak times.
Hydro One, Ontario's largest electricity utility, said crews had already responded to "significant" power outages Friday morning as high winds hit regions across the province. The utility's outage map showed roughly 30,000 customers without power as of 9 a.m.
Toronto Hydro has reminded customers to refresh their emergency kits and said additional crews are ready to support customers through the weekend.