Winter storm warning in effect for metro Montreal

Another winter storm with mixed precipitation if forecast for metro Montreal, southern Quebec and Ontario Thursday into Friday. A storm total of 20-30cm of precipitation is forecast across all regions, however some locations will receive that in liquid form and not the frozen type. This is especially true along and south of the St. Lawrence River.

A messy winter storm is expected to impact southern Quebec and eastern Ontario over the next 36 hours. Low pressure is strengthening across the Ohio valley on Thursday, and is expected to pass near or just south of Montreal on Friday. Precipitation is already overspreading the region, associated with a warm front lifting northward. Montreal can expect light snow Thursday, with a couple of centimetres possible.

As warmer air moves north, most of the precipitation will mix with and change to freezing rain and rain south of the St. Lawrence River. Enough cold air may remain in Montreal to sustain snowfall, but it will be close. The high today and Friday is expected close to 0C (32F), however  just a nudge north with the warm front and we would have all liquid precipitation.

At this time, Environment Canada has issued a winter storm warning for most of southern Quebec, including metro Montreal, Gatineau, the Laurentians and Quebec City region. The Townships are excluded as more rain is forecast there and along the US border.

In terms of amounts, expect 20-30cm for the Ottawa Valley and points north of Montreal. In metro Montreal a wide range from south to north is expected with 10-25cm. The snow will be heavy at times, reducing visibility. The Friday morning commute will be messy with mixed precipitation in Montreal. The mix should turn back to all snow mid morning in the city before tapering off late in the day.

Temperatures will begin to fall Friday, down to a low of -9C (16F) by Saturday morning. The weekend at this time looks bright and sunny, but chill, around -5C (23F). Perfect to clean up and get out and enjoy the fresh snow. The ski areas north of Montreal will benefit greatly from this storm, not so much in the Eastern Townships and New England.