It was a white-knuckle drive for motorists in the Greater Toronto Area on Thursday as the first major winter storm hit the province.

Ontario Provincial Police say there were hundreds of accidents -- mostly single-vehicle spinouts -- by mid-morning. At one point, a crash was reported every 90 seconds.

Two serious accidents on Highway 400 in the early afternoon caused massive traffic backlogs during the evening commute.

Snowfall and freezing rain warnings from Environment Canada were in effect for parts of southern and eastern Ontario on Thursday afternoon because of a low-pressure system over northwestern Pennsylvania.

The city of Toronto also issued an extreme cold weather alert on Thursday as the forecast called for the mercury to drop to -15C overnight with the wind chill factor. The alert triggers additional services for homeless people in the city.

Another two to five centimetres of snow was expected Thursday through the Greater Toronto Area while five to 10 centimetres are expected through cottage country.

"The big thing about today is there are drastically changing conditions as you go. Conditions are changing, transitioning back and forth from snow to freezing rain to ice pellets, " OPP Sgt. Cam Woolley told

Excessive speeding by over-confident drivers is the major cause of most of the accidents, Woolley said.

"Most of the crashes are where people can go fast. In the heavy traffic we're fine, but parts of the (highway), where traffic is lighter, that's where we're getting people who are getting into trouble," he said.

Woolley said drivers should avoid the following common mistakes when taking to icy winter roads:

  • Don't use excessive speed on icy roads or during poor weather conditions;
  • Don't follow closely behind other cars;
  • Avoid late breaking that can lead to a loss of control or sliding;
  • Don't take to icy roads unless aware of skid control precautions;
  • Don't drive vehicles without winter tires, broken windshield wipers or malfunctioning heat controls./>

Woolley said one life-saving tip that all winter drivers should heed is if your car starts to slide, look where you want it to go.

"Look for your escape route. Your car will go where you look. If you steer it at a tow truck, a big tree or an oncoming transport truck than that's what you're going to hit," Woolley said.

The evening commute around Toronto is expected to be relatively smooth as the system moves out of the region in the afternoon.

Winter supplies flying off shelves

The first winter storm caused many motorists to drop into retail stores and purchase proper winter supplies, such as ice scrapers.

"I broke it knocking the ice off the windshield, so I have to replace it," said one man.

An employee at a Canadian Tire in Toronto said they were expecting to sell "skids and skids and skids" of scrapers on Thursday.

Bags of salt and snow shovels were also flying off the shelves, while many drivers were buying winter tires.

"A lot of customers leave it until the end, but with yesterday's weather report, a lot of customers are coming out trying to get their tires on for safety," said Canadian Tire employee Stephen Grand.

Some residents planned to take advantage of the weather, as they were buying toboggans and sleds.

"I'm going tobogganing today -- it's my son's first Christmas," said the father of an eight-month-old.

With reports from CTV's John Musselman and Matet Nebres