A massive winter storm began hitting southwestern Ontario early Wednesday morning, as Environment Canada warned parts of the province to brace for blizzard conditions.
Snow was falling in Toronto, Hamilton, London and Sarnia while Windsor was being pounded by ice pellets. The massive weather system originated in Texas and made its way through the Midwestern United States, where cancelled flights have left travellers stranded.
More than 300 flights at Toronto's Pearson Airport were cancelled between Tuesday night at 8 p.m. and midnight on Wednesday. Travellers are advised to check with the Greater Toronto Airport Authority before heading to the airport.
All Porter Airlines flights out of Billy Bishop Toronto City Airport have been cancelled until noon.
McMaster University in Hamilton will be closed all day Wednesday. The closure includes all classes, events, non-essential operations and meetings.
Dave Phillips, a senior climatologist for Environment Canada, predicted the storm will be the worst one that Ontario has seen in three years.
Gusting winds and blowing snow will obscure visibility and make travel dangerous, said Phillips.
"It's a dangerous storm, it's huge, it's going to have a major impact. What makes it worse is the heavy amounts of snow, something we haven't seen in a long while."
The snow will be accompanied by gusting winds of 50 to 70 km/h at their strongest, Environment Canada said. The high in Toronto is forecast to be –5 C on Wednesday, and the low will dip to –9 C.
It will be "the strongest storm of the season" for urbanized areas like Toronto that are outside the Ontario snowbelt.
The weather agency had upgraded a winter storm watch in southern Ontario, stretching from Windsor to Kingston, to a winter storm warning.
Environment Canada added the blizzard warning for London, St. Catharines, Sarnia and Hamilton just after 3:30 p.m. ET on Tuesday.
By the time the storm finishes Wednesday, large swaths of southern Ontario could have snowfall accumulations of between 15 and 25 centimetres, the agency predicted.
Canadian Automobile Association spokeswoman Silvana Aceto said 3,000 assistance calls are normal on a typical winter day. However, that total can more than double during a storm as severe as the one predicted to hit Tuesday night. During a snowstorm in 2008, the Toronto CAA fielded close to 10,000 calls in one day, Aceto said.
"It's going to be messy on the roads," said Aceto. "Drivers need to plan ahead, be prepared and check that weather forecast."
Myles Currie, Toronto's transportation services director, said that with so much snow on the way, the city is stepping up its regular plowing plan.
"Earlier this year we've primarily done salting," Currie told CBC News. "With 30 centimetres expected, it will be a plowing operation for us."
Currie said plow crews will first focus on expressways, before turning to arterial roadways along streetcar lines followed by side streets.
Travel plans disrupted
More than 200 flights at Toronto's Pearson International Airport to and from the U.S. Midwest and East Coast were cancelled Tuesday and early Wednesday. Flights between Toronto and Cleveland, Columbus, Dallas, New York and Boston were the most commonly affected.
The Greater Toronto Airports Authority said 17.4 per cent of all flights to and from Pearson Tuesday through Wednesday morning at 9 a.m. ET were cancelled.
There were also numerous cancellations at Billy Bishop Toronto Airport on flights to and from Boston, Chicago and Newark Airport, which services New York City and New Jersey. Both Air Canada and Porter Airlines issued travel alerts warning people to check the status of flights to and from both major Toronto airports.
Via Rail Canada, meanwhile, warned travellers to expect heavy demand in the Ontario-Quebec corridor, although it did not expect any cancellations. GO Transit says it will be running an adjusted schedule because of the storm and is advising commuters to check its website for details.
Neither the Toronto District School Board nor the Toronto Catholic District School Board would say if there would be cancellations to schools and school bus routes.
Humber College and Centennial College have closed all of their campuses on Wednesday in anticipation of the storm.
The storm had wreaked havoc on large parts of the U.S. Midwest Tuesday. Eight states had blizzard conditions, with Texas, Missouri and Oklahoma the hardest hit. There were warnings, watches and advisories in 30 other states.
Click here for information on Toronto-area school closures, road information and travel advisories.
Kansas, Oklahoma, Missouri and Illinois declared emergencies. National Guard troops were called out in Missouri. Airlines cancelled thousands of flights and Dallas-Fort Worth International Airport closed due to an ice storm.
Chicago is bracing for as much as 60 centimetres of snow.
The Canadian Automobile Association advises motorists to avoid the roads or give themselves extra travel time on Wednesday.
It also suggests they carry:
* A fully charged cellphone.
* A winter survival kit.
* Extra clothing, blankets.
* Non-perishable food.
* Candle, in case they become stranded.