Mount Holly, some cool wording. They always do an exceptional job in the AFD.
In response to the the deepening surface low and increasing cold air
advection, the wintry mix along I-95 will quickly change back over
to snow Monday morning, and the rain/snow line will push back toward
the coast throughout the day. The strongest winds and heaviest snow
rates are not forecast to align (strongest winds likely occurring in
rain and mixing), therefore precluding the need for a Blizzard
Warning. A change over to all snow is expected on the back side of
the storm, even all the way to the coast, as the system begins
departing into Monday night.
The exact placement and strength of the low will dictate exactly
where the heaviest snow falls. The complexity of this system lies in
details of the system transitioning from an overruning precip regime
to a mesoscale banding (frontogenetic forcing) and wrap-around
precip regime early Monday. The latest 12Z guidance suite has
continued trending the f-gen banding potential a bit northward,
which suggests the greatest potential for this to occur across
portions of northern New Jersey (north of I-195) and eastern
Pennsylvania (Lehigh Valley and east/north). West of the f-gen
forcing, some guidance suggests that a dry-slot will advect in
around daybreak west of the Philly metro. The storm total snowfall
forecast was updated to reflect these features and the mixing
farther south/west. Generally 6-12" is forecast for around the
Philly metro with less south/east and more to the north. The axis of
f-gen can certainly change over the coming forecast updates. Snow
totals in the banding may exceed the broadbrush ~18-24" storm total
snowfall locally that is currently forecast in these areas.