Another blast of winter made for one of the most dangerous days of driving yet on southwestern Ontario roads.

While significant crashes involving dozens of vehicles were reported on highways in the Barrie and Port Perry areas to the north, one of the most significant crashes occurred on Highway 401 west of Kitchener.

That crash occurred shortly after 9 a.m. Thursday in the highway’s westbound lanes, west of the Drumbo Road exit.

Oxford County OPP say two tractor-trailers and a car collided, blocking all lanes of the highway.

Following that crash, two chain-reaction collisions took place, involving a total of 19 vehicles.

Eight people were taken to local hospitals – two in serious condition and six with minor injuries – and the Ministry of Environment was called in to clean up a large fuel spill.

The highway reopened shortly after 6:30 p.m.

“We’ve had several other collisions along the highway as well,” Const. Stacey Culbert tells CTV News.

“We’ve had a serious, severe storm pass through our area. If you don’t have to travel, please stay home.”

Waterloo Regional Police reported more than 50 crashes on area roads over the course of the day – predominantly in rural areas where blowing snow caused whiteout conditions.

In Perth County, OPP say they investigated 51 crashes between 8 a.m. and 4 p.m.

OPP report a total of 1,580 emergency calls between midnight and 3:30 p.m. Thursday in their West Region, which covers southwestern Ontario as far east as Wellington County.