Suggests many of us see 2-4" of snow from this.
Then after 12z, approaching positively tilted trough amplifies, with
height falls across SNE. This will provide column cooling from top
down, and rain-snow line will begin to collapse NW to SE, reaching a
BDL-ORH-LWM around 16z/11am, then into BOS-PVD around 18z/1pm. As
mid level trough evolves into a closed circulation this afternoon,
impressive comma-head forms, with all guidance indicating moderate
to heavy qpf across the region this afternoon from west to east.
Good model agreement that comma-head precip moves across northern CT
and northern MA, including Boston. Some uncertainty how far south
heavier qpf will track, possibly clipping northern RI to just south
of Boston. This matches up nicely with previous configuration of
winter headlines, with warnings continuing for northern MA, where
high terrain and colder surface temps will promote accumulating snow
more quickly. Winter weather advisories continue southward into
northern CT, northern RI and northeast MA, including the city of
Boston. Lower amounts here as it will take sometime for snow to
accumulate on paved surfaces. Snow amounts unchanged from previous
forecast, storm total approximately 4-8" across northern MA in the
winter storm warning, and 2-4" in the advisory, I-90 corridor
southward into northern CT/northern RI and northeast MA, including
Boston.
Hi res guid in good agreement on a 2 to 4 hour window of moderate to
heavy snow as the comma-head moves across the region. Snowfall rates
of up to an inch per hour (some pixels of up to 2" per hour) is
possible during this time, as modest omega becomes collocated within
the DGZ. As the surface low moves offshore this afternoon, winds
shift from NNE to NNW, and this will help surface temps cool, along
with moderate to heavy snow providing diabatic cooling via melting,
lowering ground temps, and snow accumulating on paved surfaces.
Thus, expecting the late day commute to be impacted with moderate to
heavy snow at times, across much of the region, mainly along and
northwest of I-95.