Even with warmer temperatures than what was experienced earlier in the week, Toronto's roads and highways were still slick on Saturday before the mercury plunged again in the evening.
Hundreds of accidents occurred on city highways as freezing drizzle made driving difficult and staying on the roadway even harder.
Most of the crashes occurred on Highways 401 and 404. Cars slid into the ditch or against guardrails. Around 10 a.m. a tractor-trailer jack-knifed on Hwy. 401 in the westbound lanes near Whites Road, forcing the closure of two lanes.
The worst incident happened on Hwy. 401 near Port Hope east of the city. Police closed the highway after a small car lost control and slid beneath a truck's trailer. The truck was stopped on the roadway due to another accident.
By the end of the day, Ontario Provincial Police reported 500 accidents on GTA highways due to coatings of black ice.
The result was that virtually every highway experienced delays and some stretches were brought to virtual standstills.
The icy weather also caused trouble at Pearson International Airport as jets were de-iced.
Hundreds of travellers found themselves stranded or missing connections at the nation's busiest airport. About 30 flights were delayed and 12 were cancelled due to the icy conditions.
Temperatures hovered around the -4C mark for most of the day. But temperatures were expected to fall in the evening to about -11C and stay at that frosty level through Sunday morning.
With a report from CTV's Roger Petersen
