Considerable support remains for a robust system to track into the east later in the week. Enough cold air will be available for a corridor of heavy & wet snow to affect portions of ON and QC, likely shifted just to the NW of many of the heavily-populated regions and somewhat elevation-dependent in terms of the possibility for heavier accumulations as things stand now.

This storm looks to be notably deeper than the ongoing one with the potential to intensify into the 975-980mb range as it tracks through the GL. Parts of QC which have faced snow with this current storm could be in line for a repeat wintry performance.

This is the latest version of the 12z GFS @ hour 72 – Friday AM:


Along with the 12z CMC, same timeframe:


Finally, the latest 10+cm  snow probabilities from the WPC for day 2:


Day 3:


Warmer conditions look to take hold once the low has passed and thus any snow should have limited staying power.

Farther east another round of substantial snow and associated blizzard conditions has impacted NL as expected, including additional major accumulations for areas already at the mercy of the previous low.

This is the latest summary from EC –