A vertically stacked low will be near Ohio on Sunday night, with a
diffluent flow aloft and mid level warm air advection from this
system producing snow which should at least reach the Western
Southern Tier. A surface low developing off the mid-Atlantic coast
will take over late Sunday night and Monday. A consensus track
similar to the SREF places our region along the northern fringe of
the precipitation from this system. But there is a wide spread in
model guidance, with challenges in the track of the system, and how
quickly the coastal low takes over. 12Z model consensus is slightly
north compared to previous runs, but even so the RGEM nearly keeps
the area dry through Monday. The most likely scenario drops 2-4
inches of snow across the Western Southern Tier, with amounts
tapering down to less than an inch from Buffalo to Rochester
northward. A more northerly track could support Winter Weather
Advisory headlines for the Western Southern Tier.
At least there will not be any precipitation type issues, with
thermal profiles plenty cold and moist enough to support all snow.
High pressure across Quebec will ridge into the North Country Sunday
evening, which will provide good radiational cooling conditions.
Went much colder than guidance for Sunday night, with some below
zero readings likely. It will be chilly on Monday with highs in the
mid to upper 20s in a brisk northeasterly flow.
The storm will rapidly intensify off the mid-Atlantic coast Monday
night before moving northward to near Cape Cod on Tuesday. There
will be a break in the action Monday night as the low wraps up along
the coast. However eventually moisture will wrap around the upper
low providing an increasingly moist flow across eastern portions of
the forecast area. The 12Z ECMWF/RGEM are now notably more
aggressive bringing snow back into the area east of Rochester
Tuesday and Tuesday night. This is likely to produce some
accumulating snows east and southeast of Lake Ontario, with amounts
depending on the track of the upper low. Elsewhere, just expect a
persistent northwesterly breeze with generally cold weather and
scattered snow showers.