A closed upper low is forecast to take a familiar path early next week as it treks through the Upper GL with enough cold air available on it’s NW flank to deliver another round of possible snow in NW ON and rainy / potentially severe weather in it’s warm sector to the east.

00z GFS @ hour 120 – valid Monday evening:


00z CMC, same timeframe:


Total precip from the 00z GFS ensembles @ hour 168 / day 7:


A cooldown for the central section of the country should take hold in this system’s wake, as has been depicted by the various ensembles for some time now.

Consensus is somewhat lacking for much in the way of specifics with respect to possible storminess later next week and into the following weekend but guidance is toying with the idea of a disturbance tracking farther east towards QC and the Maritimes in the Fri (May 5th) / Sat (May 6th) time period.

We’ll see if that idea stays firm over the next few days.