A jack-knifed tractor trail stalled traffic in the westbound Highway 401 lanes near the Don Valley Parkway early Tuesday morning.

The crash scene took several hours to clean up, blocking all the westbound express lanes during the morning rush hour.

According to Ontario Provincial Police Sgt. Kerry Schmidt, the driver of the truck will be charged with careless driving for the crash.

Toronto police warned on social media that roads are "very slippery," adding that the Don Valley Parkway and Gardiner Expressway have a substantial build up of snow and slush.

Clean up at Morningside Rd - ongoing<a href="https://twitter.com/hashtag/MorningCommute?src=hash&ref_src=twsrc%5Etfw">#MorningCommute</a> <a href="https://t.co/0OZpKWKnTK">pic.twitter.com/0OZpKWKnTK</a> —@OPP_HSD

"Drivers can avoid losing control by reducing [your] speed," a tweet from Toronto police's traffic services reads.

During an interview with Metro Morning, Const. Clint Stibbe stressed that while snow tires are one component of safe winter driving, he warned that too many drivers "get a false sense of security with snow tires."

"You have to be, as a driver, more responsible, more aware and more cautious."

Stibbe added that he's observed an alarming trend recently: motorists becoming too reliant on new technologies to keep them safe, rather than good driving.

Toronto police said the majority of crashes Tuesday have been single-vehicle incidents. (Tony Smyth/CBC)

"We're becoming worse drivers. We're not paying attention because we're expecting the vehicle to do the work."

Early this morning, Schmidt posted a video to Twitter to remind motorists that their commutes on the 400 series highways could be significantly slower than a clear day. He said that there was about ten jack-knifed trucks overnight, and at least two crashes involving transports on Highway 401 this morning.

Flurries moved into the Greater Toronto Area yesterday afternoon, turning to snow throughout the afternoon and overnight.