Messy weekend storm in Ontario, Quebec
Chris Scott, meteorologist
This will be a messy storm. Its already a messy forecast.
A major winter storm will affect Ontario and Quebec that is certain and our forecast team at The Weather Network continues to analyze the possibilities. Here is the latest thinking as of late Thursday:
- The primary energy for developing this storm system is just now coming onto the B.C. coast.
- The storm will begin developing Friday, east of the northern U.S. Rocky Mountains, bringing some light snow to southern Alberta and Saskatchewan along the 49th and drawing in even colder arctic air across the Prairies.
- Snow will push into Northern and Southern Ontario Saturday night. The latest computer model guidance has taken the storm track slightly farther north which means a couple of things. First, this would translate into heavier snow for the highway 17 corridor through the Sault, Sudbury and North Bay. Second, a track right through Southern Ontario would mean less snow, and more potential for mixed precipitation (a sloppier, slushy storm) near Lake Erie and Ontario including much of the QEW corridor from Niagara through Hamilton to Toronto.
- The heaviest precipitation will move into Ottawa and Montreal on Sunday. Given the current track, the forecast for Southern Quebec is a real mess with the potential for snow, ice pellets, freezing rain and rain. Ottawa will likely see mostly snow, but there is a chance for some freezing rain and even briefly rain if the system tracks far enough west.
- Warm air surges ahead of the system into the Maritimes later Sunday into Monday with rain and wind.
- How much snow could fall? Latest thinking is that the heaviest snow will likely be across the highway 17 corridor where 20+ cm (possibly aproaching 30 cm) is possible. Moving south toward the 401 corridor, amounts will likely be less still a significant system, but not likely a big snow storm for a city like Toronto.
- Sunday night into Monday could be quite wild behind the system as temperatures drop dramatically on the heels of a beastly north-northwest wind. We have some big concerns about the potential for very dangerous travel during this time in the snow belts of Southern Ontario as lake-effect squalls will rip in off Lake Huron and Georgian Bay. As well, any slushy mess that is on the ground between Toronto and Montreal will freeze up quickly Sunday night, making for some potentially icy conditions Monday morning.
Expect some refinements to the forecast through the next couple days. This is a very tough storm to nail down in terms of the amounts of the various types of precipitation, but there is no doubt that this will be a significant storm for many. Winter is off to a roaring start.