Late season winter storm to impact Montreal

Winter may not be over just yet. A strong area of low pressure will move towards southern Quebec and Ontario on Wednesday, producing an area of wet snow and rain. Some upper elevations across the Townships and northern New England/New York have the potential for over 20cm of snow, with perhaps 10cm or more in the valley locations, including Montreal on Thursday.

Special Weather Statement for all off southern Quebec and eastern Ontario. A strong late season winter storm will produce heavy amounts of snow and rain along with strong northeast winds. The storm arrives Wednesday afternoon and persists into Friday. More details will follow as the event draws closer.

For those who managed to hear my Suburban weather minute on CJAD a few weeks ago, I mentioned how common snow events were in the month of April in Montreal. So no one should be too surprised with the upcoming forecast. Winter will not go away easily, it rarely does. 

Tuesday morning is quite frosty across southern Quebec, with below freezing morning temperatures, and some ice fog and mist around Montreal. The day will be sunny and pleasant, with a high near 10C (50F). Enjoy it, the wheels fall off after today.

Strong low pressure over the southern Rockies will deepen as it moves towards the central Great Lakes. Widespread precipitation will move across Ontario and eventually into Quebec. Heavy rain will fall along the lower lakes and St. Lawrence Valley, before transitioning to wet snow late Wednesday into Thursday. A second storm is forecast to develop along the eastern seaboard and become the dominant system Thursday as it meanders into coastal Maine.

That storm will produce cold northeast winds in the St. Lawrence Valley, gusting up to 50km/h and producing colder temperatures. This will allow for the precipitation to remain as wet snow on Thursday. At this time, significant accumulations of 20-30cm are likely over higher elevations, as well as the upper Ottawa Valley, with 10-15cm in southern valley locations, including Montreal. The snow will taper to flurries on Friday. Temperatures will marginally cold enough for snowfall, so these numbers may be adjusted.

The wet nature of the snow may cause power outages and very poor road conditions on Thursday, especially in the Eastern Townships, Ottawa Valley, Adirondacks and Green Mountains.

All locations will have blustery winds and cooler-than-normal temperatures from Thursday into Saturday. Conditions will improve on Sunday and remain that way into Eclipse Monday. Great weather is anticipated at this time for viewing the eclipse in Montreal.