Environment Canada has issued snow squall warnings for Toronto, Pickering, Mississauga, Oshawa, Brampton, Caledon, Vaughan, Richmond Hill, Markham and Orangeville.
The latest batch of warnings, issued shortly after 6 p.m., follow a day where poor visibility and snow-covered roads were reported in a number of areas, including Highway 400 through Vaughan and Highway 427 north of Highway 401.
Police urged motorists to drive with extra caution after dozens of collisions or spin-outs were reported during a flash freeze that created a slow and dangerous morning commute.
Toronto police traffic services Const. Clint Stibbe said motorists were largely to blame for the smash-ups.
“They are completely forgetting how to drive today and they’re expecting that their car is going to stop on a dime. Unfortunately, that is not the case,” Stibbe told CP24 after he responded to a crash.
Some roads appeared to be dry but were covered in ice.
Stibbe urged people to slow down and leave extra room between vehicles.
“We are finding a lot of glare ice on the roadways and people are driving far too fast for the conditions,” he said.
At one point, police shut down a section of the Gardiner Expressway's westbound collectors due to a sheet of ice that was compared to a skating rink.
The lanes and ramps reopened after salters went through, but Stibbe later said that strong winds were blowing the salt off many roads.
Nearby, police were forced to close Lake Shore Boulevard's ice-covered westbound lanes at Ellis Avenue after a car crashed into a pole.
In Brampton, Goreway Drive was closed south of Queen Street after a three-vehicle crash sent a young child to hospital with a serious head injury, Peel Regional Police said.
Near the intersection of Burnhamthorpe and Dixie roads in Mississauga, salt trucks were called in after vehicles, including two buses, failed to climb an icy hill.
Wet roads became icy as the temperature dipped below the freezing mark Thursday morning. By 7 a.m., the temperature had dropped by 13 degrees, from 10 C at midnight to -3 C.
The freeze occurred after a two-day warm spell gave southern Ontario a break from winter.
Less than 24 hours after almost a dozen communities set record highs with double-digit temperatures, the cold returned with strong winds and snow.
CP24 meteorologist Chris Potter said the temperature will be steady near -9 C in the GTA Thursday night.
The cold air was ushered in by a Colorado low that tracked across the province, bringing an end to a record-setting warm front.
Daytime highs of -6 C are expected in Toronto on Friday and Saturday.
Record-setting weather
During the warm front, at least 12 weather stations set warm weather records for Jan. 30, including two in the GTA.
The weather station at Pearson airport recorded a high of 14 C, breaking a seven-year-old record of 9.1 C. At Buttonville airport, a temperature of 13.5 C broke a record of 8.9 C, which was set in 1988.
Burlington, Bancroft, Collingwood, Cobourg, Goderich, Mount Forest, North Bay, Port Weller, Windsor and Wiarton also set new records, said CP24 meteorologist Chris Potter.
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