Ontario Provincial Police were urging motorists to slow down and drive with care on ice-covered roads north of Toronto on Friday after storm bringing snow and freezing temperatures was blamed for several collisions.

One of the most significant crashes involved a tractor-trailer on Highway 400 in Bradford West Gwillimbury, and resulted in a major traffic jam that backed up southbound traffic for almost six kilometres.

Traffic is flowing again between highways 88 and 89, but the southbound lanes and one northbound lane were closed at one point until a heavy tow truck hauled the transport truck away from the scene, and crews cleaned up a diesel spill and replaced a heavily-damaged guardrail.

No one was injured when the tractor-trailer veered out of its lane, struck the steel median and wound up straddling the guardrail dividing the northbound and southbound lanes shortly before 5 a.m.

Anyone with information about the single-vehicle crash is asked to call the Aurora OPP detachment at 905-841-5777.

OPP responded to several collisions along that slick stretch of Highway 400, including reports of vehicles sliding into the ditch, in addition to a serious collision on Highway 11 near Huntsville.

OPP said most roads north of Aurora were covered in ice because of a wintry blast of weather that moved into the region Thursday and lingered overnight, largely affecting cottage country.

Power outages reported

Power outages occurred in Bracebridge and Orillia, OPP said Friday morning.

Snow flurries were reported from northern edge of the Greater Toronto Area to communities north of Georgian Bay, but some communities were blanketed with up to 20 centimtres of snow because of squalls that moved in from Lake Huron or Georgian Bay.

The heaviest snow squall activity moved into the Midland and Orillia regions early Friday morning before Environment Canada cancelled snow squall watches and warnings shortly before 5 a.m.

Submit your photos of the snow to CP24's MyBreakingNews or email them to now@cp24.com.

Weekend forecast

Toronto was spared from the storm's wrath and appears to be in store for a decent but windy weekend as the annual Santa Claus Parade comes to town.

Environment Canada is predicting a high of 7 C on Friday, high of 11 C on Saturday and high of 13 C on Sunday, when the parade takes over some downtown streets. As many as one million people are expected to attend the event.

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