There was no spring in sight — at least not in Central and Eastern Canada today.

A late-winter storm packing between 10 and 25 centimetres of snow made for sloppy travelling conditions Wednesday from southern Ontario to Newfoundland, even contributing to a 20-car pileup on a major Ontario highway.

Environment Canada issued weather warnings throughout southern Ontario, southern Quebec and in most of the Atlantic provinces.

Snowy conditions clogged highways leading into St. John’s, and there were numerous reports of collisions. The St. John’s Morning Show’s traffic reporter reported whiteout conditions in some parts and numerous slippery patches of roads in the pre-work hours.

In Toronto, where temperatures were predicted to slide from above-zero temperatures to –5 C, heavy wet snow began falling as day broke over the city. Toronto Pearson International Airport was already advising passengers to check on the status of their flights before heading to the airport and said some flights had already been cancelled.

By the early afternoon, Pearson airport reported that 120 departing and 115 arriving flights had been cancelled.

Areas east of Toronto, including Kingston and Montreal, were bracing for 20 to 25 cm of snow and gusty winds, but the nasty weather wasn’t expected to hit until around 11 a.m. and 1 p.m. ET.

Ontario Provincial Police received 255 calls for service between 9 a.m. and 1 p.m. in the Greater Toronto Area alone.

OPP also attended at a 20-car pileup on Highway 401 near Woodstock, Ont., with expectations the highway would remain shut down from the 401-403 split well into the evening. As many as a dozen tractor-trailers were involved in the pileup, and about 40 vehicles not involved in the crash were stuck in the area.

Toronto snow storm March 12 commuter

After a day of seasonal, spring-like temperatures, parts of Ontario, Quebec and the Atlantic provinces got a wallop of snow on Wednesday. A storm passing over southern Ontario deposited up to 15 cm in parts of the Greater Toronto Area causing traffic snarls and flight cancellations. (Evan Mitsui/CBC)

The severe weather is being caused by an intensifying low pressure system that’s moving south into the U.S., allowing colder air to settle in over Canada, Environment Canada said.

If the return of the cold wasn’t enough, northeasterly winds — gusting up to 80 km/h in places — could cut visibility and create blizzard-like conditions in southern Ontario.

The wind is also set to stick around on Thursday, plunging areas like Toronto back into the negative double-digit temperatures when wind chill is factored in.

Areas in Southern Ontario under a winter storm warning include:

  • Brockville – Leeds and Grenville.
  • Cornwall – Morrisburg.
  • Dunnville – Caledonia – Haldimand.
  • Elgin.
  • Kingston – Prince Edward.
  • Niagara.
  • Simcoe – Delhi – Norfolk.
  • Stirling – Tweed – South Frontenac.
  • Windsor – Essex – Chatham-Kent.

The city of Hamilton was expecting up to 15 cm of snow and was under a wind warning, with winds gusting up to 60 km/h expected.

Flight cancellations

Check airline websites for flight statuses and other weather-related updates:

Much of southeastern Quebec is expected to experience the winter weather as well. Environment Canada warned of:

  • Up to 40 cm of snow along the Appalachians.
  • Between 15 and 20 cm of snow over the Upper St. Lawrence and over the Gaspé Peninsula overnight.
  • Strong winds in areas experiencing snowfall as well as several areas along the middle and Lower St. Lawrence.

In Nova Scotia, up to 40 mm of rain was expected to fall Wednesday morning, with the highest amounts through the Annapolis Valley, according to Environment Canada. A winter storm warning was also in place for Colchester County North and Cumberland County North and Cobequid Pass.

Much of New Brunswick was also under a winter storm warning, while Kent County, Kouchibouguac National Park and Miramichi and area were under a blizzard warning.

March Break travel delays

Newfoundland car in ditch

A car wound up in the ditch during a slick morning commute in the St. John's area on Wednesday. (Scott Jackson/CBC)

By 11 a.m. ET,  16 per cent of flights had been cancelled at Toronto's Pearson airport, most within North America.

Airport officials tweeted a warning that expected snow could lead to March Break travel delays. The airport urged travellers to check their flight status.

Air Canada issued travel alerts at several airports across Ontario, Quebec, Prince Edward Island and New Brunswick due to the forecast.

WestJet issued a travel advisory for Eastern Canada, namely southern Ontario and Quebec. The company warned passengers to check their flight status before heading to an airport.