The first winter storm of the season struck southern Ontario on Monday night, blanketing the roads in snow and ice and causing hundreds of car accidents across the region, before pushing into Quebec.

Ontario

By Tuesday morning, rain had turned Toronto's sidewalks into a mess of slush, but weather warnings remained in effect in effect for a winter storm in the Ottawa area, and freezing rain elsewhere in the province.

According to the Ontario Provincial Police, there were more than car 300 crashes on southern Ontario highways on Monday night. In Toronto alone, there were 130.

The blast of winter blew up into the region from Texas, where the storm system spawned deadly tornadoes earlier this week.

Environment Canada says the storm is currently tracking towards the Great Lakes, and is leaving up to 30 centimetres of snow in some areas and up to 10 millimetres of ice build-up in others

In areas such as the City of Ottawa, blowing snow could cause "near-zero visibility" at times, making driving difficult, the agency warned.

The precipitation is expected to "taper" on Tuesday afternoon.

Quebec

Meanwhile, much of southern Quebec remains under a winter storm watch, with the weather agency calling for between 15 and 40 centimetres of snow in Montreal by Tuesday evening.

The weather could also cause transport delays there, Environment Canada says.

Also in Quebec, the St. Lawrence Valley region can expect up to 60 kilometre-per-hour winds on Tuesday, according to the agency.

The City of Montreal is urging residents to consult the Info Neige app or website for information about snow-clearing and parking during the storm.

Atlantic Canada

Further east, in New Brunswick and Nova Scotia, a low pressure system from the Eastern U.S. has prompted Environment Canada to issue snowfall warnings across the southern parts of the provinces.

The agency says 15 to 25 centimetres of snow and ice pellets can be expected for western and central Nova Scotia before the storm quiets overnight.

A full list of Environment Canada warnings, watches and statements is available on the agency's website.