A winter storm is creating “particularly difficult” conditions across the roads in the Montreal area Thursday, with several accidents reported.

The snow system, which is expected to bring between 10 and 15 centimetres of accumulation by the evening, has already caused multiple vehicle pileups and collisions, police in Longueuil said in a post on X Thursday morning.

STM said in an X post that while its buses are running, “road conditions are particularly difficult.”

Furthermore, the REM said service has been interrupted between Bois-Franc and Ville-de-Mont-Royal stations in all directions. In a post on X, it said it does not know when service will resume and shuttle buses will be available.

Get daily National news

Get the day’s top news, political, economic, and current affairs headlines, delivered to your inbox once a day.

Environment Canada has issued a yellow alert for Montreal, saying visibility will likely be reduced at times.

“Prepare for quickly changing and deteriorating travel conditions,” it added.

The Montreal area is not the only major Canadian region to experience adverse weather Thursday.

Environment Canada upgraded its snowfall weather alert for the Greater Toronto Area after the region was hit with a major snowstorm.

The weather agency initially classified it as a yellow alert, but upgraded it to an orange alert just before 8 a.m.

Environment Canada said snowfall amounts of 20 to 30 centimetres is expected for the area.

It warns of reduced visibility and heavy snow, as well as local blowing snow. The snow is expected to continue through the morning and taper off late Thursday afternoon.

Temperatures also dropped significantly overnight, reaching minus double digits. Toronto woke up to -22 C with the wind chill on Thursday morning.

Environment Canada has recently started using a colour-coded system to make it easier to understand the severity of extreme weather and any risks that people might need to know about.

Orange alerts are issued when severe weather is likely to cause significant damage, disruption or health impacts. Impacts can be major, widespread and/or may last a few days.

Yellow alerts are typically the most common and red alerts are rare.

— With files from Global News’ Gabby Rodrigues

&copy 2026 Global News, a division of Corus Entertainment Inc.