More snow followed by arctic air for Montreal

The mounds of snow are growing across the suburbs of Montreal. Crews have been hard at work carting away the snow from three separate storms over the last week. More is on the way Thursday, with 5 to 10cm expected over southern Quebec. (ValleyWeather Photo)

Another shot of snow is on the way for southern Quebec, adding to the 45 to 55cm that has fallen since last Thursday. Low pressure over the Ohio Valley will rapidly move across central New England on Thursday and out into the Atlantic. The storm will be quickly followed by a surge of arctic air late in the day.

Snow will spread into Montreal before the morning commute Thursday, and taper off to flurries in the afternoon. Environment Canada is aiming low for Montreal, calling for 2-4cm total accumulation. I feel it will be more in the order of 5 to 10cm in southern Quebec and eastern Ontario, with up to 15cm along the US border. The snow may be enhanced briefly during the morning hours as an arctic cold front cuts across the region. Winds will increase out of the northwest and temperatures will plummet in the afternoon and evening hours. The high Thursday will be reached early in the morning in Montreal, at -1C (30F). The temperatures will fall into the -20s by Friday morning across our region. Most of central Quebec is under extreme cold warnings, for windchill readings near -40C. Montreal can expect windchill values well into the -20s.

Friday will be blustery and cold, with daytime highs struggling to reach -12C (10F). The weekend will be milder once again, but unsettled with plenty of clouds and flurries around. As we head into next week, another winter storm may impact Montreal by Tuesday with measurable snow.