Environment Canada has posted a Heavy Snow Warning for Montreal and most of southern Quebec as well as extreme eastern Ontario including Brockville to the Quebec Border and the Ottawa region. Low pressure over Kentucky this morning will rapidly deepen as it moves to near Burlington, Vermont overnight and close to Quebec City on Wednesday. A sharp temperature difference will accompany this storm with mostly rain across New England and New York as well as southern Ontario. However from the St. Lawrence Valley north, heavy wet snow is expected along with strong northeast and then northwest winds. The wet snow could accumulate 15-20cm (6-8 inches) in a band running from just north of Ottawa across the Laurentians. Here in Montreal as well as Ottawa a general 10-15cm (4-6 inches) snowfall is forecast mixed at times with rain or freezing rain. Temperatures will be near freezing for the duration of the storm followed by a rapid drop in temperatures on Wednesday. An arctic front will sweep the area with dropping temperatures from 0C to -9C in a matter of hours Wednesday with any rain changing to all snow including in New York and Vermont. A rapid freeze up is expected Wednesday region wide including Toronto and areas south of Montreal that had received mostly rain. Roads will become very icy Wednesday with dropping temperatures and strong northwest winds up to 60km/h. Skies will clear Thursday before more snow Friday.
The bottom line is if you have to travel do it today.