The Greater Toronto Area (GTA) is bracing for what city officials are calling the most significant winter storm of the season so far.

Follow CP24.com for live updates on the storm’s progress, road conditions, cancellations and other weather-related information.

9 P.M.

Ontario Provincial Police continue to deal with crashes on highways. In a video update, Sgt. Kerry Schmidt said a jackknifed transport truck is blocking three southbound lanes on Highway 400 just south of King Road.

"We have problems really all across the GTA. The plows and soldiers are working hard to keep those highways clear," he said.

"If you can avoid travel today, please wait until the system passes. Let the plows do their job. If you're on the roads, please drive carefully. Give yourself lots of space and get home safely."

Meanwhile, as of 8:55 p.m., 26.75 per cent of departing flights at Toronto Pearson have been cancelled.

The TTC has also cancelled all express buses due to the weather.

6:30 p.m.

The TTC has stopped service on Line 3 Scarborough due to weather conditions. Shuttle buses are on the way. Meanwhile, the transit agency says its website is back online.

5:30 p.m.

A hectic and potentially dangerous evening commute is underway across the GTA, as wet, heavy snow continues to fall, causing slippery road conditions and reduced visibility.

Commuters are being urged to use caution while driving, expect major delays and stay off the roads if possible.

Ontario Provincial Police (OPP) Sgt. Kerry Schmidt says the conditions on GTA roads are extremely hazardous and will only get worse as the evening goes on.

“We’re dealing with about 40 crashes right now across the GTA,” Schmidt told CP24 this afternoon.

“Fortunately, none of them are reported as any serious injuries… we’ve got lots of problems; officers are responding as quickly as they can.”

Schmidt says that as the wet snow continues to fall, it’s being melted by salt on the roads, and that water is then partially freezing due to the cold temperatures, causing slick roads.

“Once this system clears, which will hopefully be either later tonight or tomorrow, we’ll have the ability to resume travel but right now, in the height of it, it is not the time to be driving. It is slippery, slick and icy, and the salters and plows can’t keep up with the continued accumulation that keeps falling,” Schmidt says.

“Get off the highway and get home as quickly and as safely as you can, and wait for the system to pass – it’s not going to be fun out on the roads this evening.”

Meanwhile, the TTC says its main website is currently down due to the weather conditions. It doesn’t say what exactly caused the outage or when it’s expected to be resolved.

With heavy snowfall expected through the night, a number of GTA school boards have announced cancellations for this evening and tomorrow. Here’s a full list of bus and school cancellations in effect for Thursday.

So far, The York Region (YRDSB) and York Catholic (YCDSB) District School Boards have cancelled all student transportation for tomorrow, however schools will remain open.

4:30 p.m.

As inclement weather continues to impact travel across the GTA, Pearson Airport is reporting that over 25 per cent of scheduled arrivals and departures have been cancelled so far today.

4 p.m.

The list of weather-related cancellations is growing steadily as the “most significant” winter storm of the season so far continues to dump snow on the GTA.

York Region District School Board (YRDCB) is the latest school board to cancel transportation services for tomorrow, joining York Catholic District School Board (YCDSB).

Both boards say schools will remain open on Thursday.

Meanwhile, Toronto Metropolitan University and Sheridan College have cancelled all in-person classes for the remainder of the day.

Sheridan says all of its campuses are closed as of 4 p.m., however all virtual classes will continue on schedule.

The city of Toronto has announced that, due to severe weather, recreation centres and indoor arenas will close as of 6 p.m.

“Instructional and drop-in programs as well as permits are cancelled as of 4:30 p.m. and classes will be made up at the end of the session, if possible,” the city said in a tweet.

“After-school programs and facilities with childcare centres will run as scheduled. Skating lessons at outdoor artificial ice rinks are cancelled as of 4:30 p.m.”

As road conditions continue to deteriorate, commuters this evening may encounter hazardous conditions such as reduced visibility and slippery road surfaces.

Drivers are advised to take precautions, expect delays and stay off the roads if possible. 

Earlier today, city officials said Toronto's fleet of plows would be deployed on major routes across the city this afternoon or evening, once at least two centimetres of snow accumulates on the roadways.

“Our service levels for plowing are, for expressways; about two centimeters, for our arterial and collector roads; five centimeters, and for the local residential roads, it's eight centimeters,” said Director of Operations and Maintenance with Toronto Transportation Services, Vince Sferrazza.

“For the sidewalks, we will start at two centimeters and for the separated bicycle lanes, we’ll start salting and plowing at two centimeters as well. So we anticipate that we'll be plowing this evening.”

Storm

3 p.m.

As snow begins to accumulate across the GTA, multiple school boards have announced cancellations, and the TTC says it will take 41 bus stops out of service overnight.

The York Catholic District School Board (YCDSB) has cancelled all student transportation tomorrow, however schools will remain open.

“Exams, tests, quizzes, excursions, charter trips, school programs, co-curricular activities, evening presentations, workshops, in-services and parent meetings (i.e Identification, Placement, and Review Committee Meetings, IPRCs) are cancelled for that day and will be rescheduled,” the school board said this afternoon.

Toronto’s Catholic District School Board (TCDSB) says it will continue to monitor the weather situation and will inform parents of any bus cancelations by 6 a.m. tomorrow.

Meanwhile, the Halton Catholic District School Board (HCDSB) has cancelled all sports practices, after school clubs, programs, meetings and athletics scheduled to take place this afternoon and evening, however Community Use of Schools permits remain open.

The TTC says it’s implementing its enhanced Severe Weather Plan to ensure it’s able to continue providing uninterrupted service. It also announced a number of bus cancellations overnight.

Forty-one bus stops located in “hilly areas that are difficult for buses to navigate in snow and ice” will be taken out of service overnight tonight.

“The TTC is preparing for today’s expected winter storm and is ready to safely get those who must travel today and tomorrow to and from their destinations,” the TTC said in a statement this afternoon.

“Based on the latest forecasts, this storm is likely to make surface travel challenging, so the TTC is encouraging those who need to travel to use transit to get to their destination in a safe and reliable manner.”

Currently, the Line 3 Scarborough SRT is operating as usual.

“However, as the weather turns to a snow event, the line will be closed and fully replaced with buses until weather allows for it to re-open,” the TTC said.

“The entire streetcar overhead network and vehicles have been treated with an anti-icing application. Should any issues arise on 512 St Clair, the route will be serviced with replacement buses.”  

Winter storm

1 p.m.

Heavy snowfall is expected to continue throughout the afternoon across southern Ontario, and the GTA is preparing for what could be a dangerous evening commute.

The city of Toronto’s Transportation Service has a fleet of over 1,000 vehicles dedicated to salting, plowing and snow-clearing, and plows are expected to be out on the roads later this afternoon once at least two centimetres of snow has accumulated on the roadways.

Transportation Services’ Director of Operations and Maintenance, Vince Sferrazza says that snow removal may also be required in the coming days.

“It's going to be heavy snow, and if required, we will likely have to do some actual snow removal,” he said.

“Not like what we did last January when we had to remove 180,000 tons of snow, but we're likely going to have to do some snow removal for bicycle lanes, for dedicated routes such as TTC, streetcar routes, high pedestrian areas, bus routes and bus stops.”

Elsewhere in the GTA, the city of Burlington has announced it will close all of its recreational facilities, its downtown transit terminal and City Hall at 2 p.m.

“The city of Burlington makes every effort to keep our facilities open during regular business hours; however, when unsafe weather conditions occur, the city must close facilities,” the city said in a tweet.

“Also due to weather, the in-person public service counters at Halton Court Services will be closed at 2 p.m.”

12 p.m.

Across the GTA, light snow continues to fall and is expected to become heavier as the day goes on.

“We’ll start to see things get a lot messier in just a few hours,” said CP24's weather specialist Eden Debebe this morning.

“We’ll start out with light snowfall but as the day goes on, it’ll steadily get heavier. We’ll see winds picking up, gusting upwards of 45 or 50 km an hour and in some areas, even gusting up to 60 km an hour. It’ll cause reduced visibility on the roads, making conditions slick, so it’ll be a very dangerous commute on your ride home tonight.”

Toronto’s Pearson Airport has advised travellers to be careful as road conditions are expected to deteriorate. It’s reminding travellers to check their flight status before heading to the airport.

Go Transit users may also want to check train departure times as Metrolinx announced they’d be on a reduced and adjusted schedule due to the weather today.

“During severe weather, you may experience delays but our goal is to get you to your destination safely,” Metrolinx said in a statement. 

10:30 a.m.

Snow has started to fall across the GTA and is expected to intensify over the course of the afternoon and through the night.

The City of Toronto announced it would open several warming centres tonight at 7 p.m., with all spaces available by walk-in.

The three locations are Scarborough Civic Centre at 150 Borough Drive, Metro Hall at 55 John Street and Mitchell Field Community Centre at 89 Church Avenue.

9 a.m.

Environment Canada has issued a snowfall warning for the city of Toronto as well as the regions of Peel, Durham, Halton and York.

The warning says to expect significant snowfall beginning this afternoon, with total accumulation of around 20 centimetres.

The rapidly accumulating snow may cause reduced visibility and hazardous conditions during this evening’s commute, the warning says.

“A Texas low will bring heavy snow to the area beginning early this afternoon. Heavy snow will taper off to flurries Thursday morning,” the warning goes on to say.

“There will be a significant impact on rush hour traffic in urban areas. Allow extra time to reach your destination.”

7:30 a.m.

Director of Operations and Maintenance with Toronto Transportation Services Vince Sferrazza spoke to the media outside a North York winter depot Wednesday morning to provide an update on the city’s storm preparations.

Vince Sferrazza

“All of our contractors and crews are getting ready for the upcoming storm that we expect to arrive early this afternoon,” Sferrazza said.

“Our contractors are getting our salt domes all replenished so that all the vehicles and all the equipment can get all their salt and get it deployed quickly.”

Sferrazza said the city anticipates total snowfall accumulation of at least 20 to 25 centimetres.

“This is going to be, most likely, the most significant winter event we've had this winter season with respect to snowfall accumulation,” he said.

Sferrazza added that crews began applying liquid brine to various roadways across the city last night in preparation for the snow.

“Those locations would include the expressways, hills, bridges, and high priority intersections. And this is where we're applying a formula of both water and salt onto the road, which helps for a number of reasons,” he said.

“One, it will prevent the ice from formulating so quickly, especially on the bridges. And two, it'll allow the salt, when it's applied by the salt spreaders, to stick to the road so it doesn't splatter as much across all the various lanes, sidewalks and so forth. So, it helps us in getting that first round of salt down on the road so it can build that layer of salt so it can start thawing the snow.”

But, Sferrazza says, the city will likely switch over to plowing this afternoon, as snow is expected to fall quickly and heavily.

“Because we anticipate that the snow is going to come relatively heavy and it's going to come over a period of about 16 to 18 hours, we will likely be transitioning over to plowing very quickly, so you're going to see us plowing all of our roads fairly quickly this afternoon,” he said.

“The one thing I want to stress is that this is going to be a multiple round and multiple pass event. The equipment; the salters, the plows, the sidewalk machines for the bicycle lanes, all of them will have to complete numerous rounds throughout the next few days.”