wpc heavy snowfall disc
spreading snow across northern NYS into northern New England as
mid-level troughing digs into western NY/Lake Ontario and a
persistent band of FGEN translates eastward into the region. At the
same time, a system in the Southeast will start to lift
northeastward along the coast, bringing a surge of moisture
northward on strong 50-60kt winds at 850mb across Long Island.
Aloft, jet will start to buckle a bit and increase quite smartly to
over 150kts across Quebec, with much of northern New England in
the right entrance region of the jet. Surface high pressure will be
split to the north and east of the region, but a low pressure
track along and off the New England coast should maintain some
northeasterly cold air drainage into interior sections. This could
set up a narrow band of sleet and/or freezing rain in between snow
over interior locations and rain along the coast as mild SE flow
overrides the marginally sub-freezing interior locations. Snowfall
could be quite heavy at times, with HREF probs >1"/hr already
~60-80% early Saturday over northern NY/VT/NH, with snow continuing
eastward thereafter into Maine (beyond the 12Z HREF end time).
Snow ratios may be quite variable as the system evolves and may
also be dependent on time of day as well (esp with lower rates
outside the favored areas). Regardless, significant accumulations
are possible from the Adirondacks into the northern Green/White
Mountains and into northern Maine. There, WPC probabilities for at
least 12 inches of snow Sat-Sun are high (>70%). Lower amounts
around 4 inches are possible as far south as about I-90 across NY
and then turning northeastward across south central NH to coastal
Maine, especially west of I-95 in southern Maine.