I just spent about an hour digesting the latest 00z computer models and upper-air data then drawing the maps here at home.
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Confidence is now fairly high that the initial primary storm tracking across the U.S. Midwest will remain well organized as it tracks over Lake Erie then toward southern Lake Ontario before getting absorbed by the rapidly strengthening coastal storm later Friday.
My initial numbers were lower for many areas due to some uncertainty. Now that things are becoming more clear, I feel more confident in taking some numbers up.
The track of 850 mb low associated with the primary storm is ideal for significant snow in the outlined areas, including the GTA. Also, with cold air in place, the snow ratios will be higher than normal, which has to be factored in, especially from the GTA on north and northeast.
I expect a general 23-28 cm for Toronto itself, with the usual higher amounts just outside of the city.
There will be an initial band of overrunning snow Thursday night, especially north and west of the GTA, then the steady snow will get into the GTA very late Thursday night and continue through Friday morning before slowly tapering off later Friday afternoon as the best snow focuses between Peterborough and Cornwall.
There may also be a little lake enhancement to the snow near Hamilton, Ont., early Friday, though 850 mb temps will be marginal.
There will be a sharp decrease in snowfall from southwest to northeast near the Montreal area as the snow from the primary storm will begin to weaken as it encounters drier air and best dynamics focus toward southern New England.
Blizzard conditions are likely Saturday across parts of the Maritimes with the heavy snow and strengthening northeast winds.
It looks like I may encounter some travel issues Friday afternoon as I head up toward Mt. St. Louis/Moonstone, but at least the skiing looks great for Saturday!
Forecast pattern clues through most of July.
Thunderstorms this weekend and a look at the long range.
Some new clues to the summer and fall season.
Amplified jet stream pattern will keep forecasters on their toes over the next week or so.
Weather pattern clues for the next several weeks.
A look back at May and the spring of 2016 in terms of temperature departures.