The GTA entered another deep freeze Monday night as the temperature plummeted thanks to a sharp Arctic cold front that is being dragged across the region by a winter storm.

Because wind chills as low as -41 are expected overnight, Environment Canada issued a wind chill warning and the City of Toronto issued an extreme cold weather alert to increase services for the homeless.

The cold front is bringing the same teeth-chattering temperatures and wind chills that GTA residents shivered through last week.

The temperature will drop to about -25 C overnight with bitter wind chills of -38 to -41 into Tuesday morning.

The cold front arrived after a winter storm brought snow, freezing rain and rain Sunday night and early Monday morning, forcing motorists to contend with a flash freeze that left a layer of ice over many roads and sidewalks.

The ice created tricky driving conditions throughout the region as students headed back to school and many people returned to work after the Christmas break.

At the height of the morning commute, police responded to several crashes or vehicles that skidded off the road. In the GTA alone, Ontario Provincial Police officers responded to about one call every two minutes, a spokesperson said.

North of Toronto, a tractor trailer jackknifed on Highway 400, closing the southbound lanes south of Innisfil Beach Road. The driver was trapped in the truck for about an hour. Paramedics transported him to hospital, where he was receiving treatment for serious but non-life-threatening injuries.

The weather created all kinds of problems for motorists. CAA South Central Ontario said it received thousands of calls for help, resulting in wait times of more than an hour.

Flights cancelled or delayed

The weather also was a headache for airline customers, including dozens who spent hours aboard stranded planes on the tarmac at Pearson International Airport.

Because of a backlog, the planes were forced to sit on the tarmac and wait for gates to open so the passengers could exit.

Karen Lopez told CP24 her plane sat on the tarmac for about four hours after flying in from San Francisco, where takeoff was delayed due to mechanical issues.

Lopez said she passed the time by sending and reading tweets, and watching shows on the plane’s in-flight entertainment system.

Most airlines have issued travel advisories and they are asking passengers to confirm their flight status before heading to the airport because there are dozens of cancellations or delays.

Madden said the airport brought in extra crews for snow removal and plane deicing, and it was “full hands on deck” inside the terminals.

Police ask drivers to stay off streets, highways

Whiteout conditions west of the city have prompted police to ask motorists to stay off streets and highways.

In a release sent out at around 10 p.m., Halton police said they are dealing with a number of accidents in the Milton and Halton Hills areas.

Motorists that can avoid driving tonight are being encouraged to do so.

Blowing snow and poor road conditions have led to dangerous conditions on a number of roadways, including Steeles Avenue, #5 and #10 side roads and Ninth and Tenth lines, police said.

School boards warn of possible morning delays

School boards in the city are warning parents of potential delays Tuesday morning as a result of the frigid conditions.

In separate tweets sent out Monday, both the Toronto District School Board and Toronto Catholic District School Board cautioned of possible bus delays.

Students are being encouraged to bundle up and parents are being advised to monitor communications from the school boards for weather-related updates.

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