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:
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 – http://weather.gc.ca/warnings/weathersummaries_e.html
NEWFOUNDLAND AND LABRADOR
Weather summary for Newfoundland issued by Environment Canada at 11:28 a.m. NDT Tuesday 4 April 2017. Discussion. An intense low pressure system tracked very slowly south of Newfoundland over the past couple of days and is now moving away to the southeast today. Snow associated with this system spread across most of Newfoundland Sunday night and continues to fall over many parts of northeastern, central and eastern Newfoundland today. Over eastern Newfoundland, the snow changed through freezing rain to rain on Monday and then eventually back to snow. Very strong north to northeasterly winds also accompanied this system, causing blizzard conditions over many areas. This is a preliminary bulletin up to 10:30 A.M. NDT. As the snow continues to fall today, additional snowfall accumulations will be added to some of the values below and will be included in an update after the storm ends. The following is a summary of weather event information received by Environment and Climate Change Canada. 1. Summary of snowfall in centimetres: Gander Int'l Airport: 59 Terra Nova National Park: 55.8 * Twillingate: 38.2 * St. John's Int'l Airport: 27.8 St. Lawrence: 21.1 * Badger: 19.3 * La Scie: 17.3 * * Amounts are based on water equivalent. 3. Summary of peak wind gusts in kilometres per hour: Sagona Island: 165 Green Island (Fortune Bay): 145 * Burgeo: 141 Northwest Head: 139 * Burgeo Highway Road Weather Site: 122 * Pass Island: 120 * Port aux Basques: 115 Allan's Island: 115 * Bonavista: 113 Twillingate: 113 St. Pierre: 102 Gander Int'l Airport: 100 St. Lawrence: 98 Cape Race: 96 St. John's Int'l Airport: 89 * Private station. Please note that this summary may contain preliminary or unofficial information and does not constitute a complete or final report. End/ASPC