Meso discussion from SPC, would seem to support there's issue with drier air.
Mesoscale Discussion 0149
NWS Storm Prediction Center Norman OK
0933 PM CST Fri Feb 16 2024
Areas affected...Northeast West Virginia to western New Jersey
Concerning...Heavy snow
Valid 170333Z - 170730Z
SUMMARY...A swath of moderate to heavy snowfall will continue to
spread east across parts of the Mid-Atlantic over the next several
hours.
DISCUSSION...A swath of moderate snowfall continues to spread east
from the upper OH River Valley region into the Mid-Atlantic based on
recent regional reflectivity composites. Transient organized snow
bands continue to be observed within this broader zone, resulting in
visibility reductions from 1/2 to 1/4 mile and steady snowfall
accumulations based on recent snow reports from the region.
Favorable phasing of synoptic ascent ahead of the approaching
shortwave trough and strong isentropic and frontogenetic lift within
the 925-700 mb layer, which has been driving this activity so far,
is expected to persist as the system pushes towards the East Coast
over the next several hours. Latest forecast guidance depicts
reasonably high probability in snowfall rates between 1-2 inch/hour
across portions of the Mid-Atlantic region (and possibly as far east
as the NJ coast) through 08 UTC. Based on observed trends, this
depiction seems fairly reasonable. One caveat is a lingering
warm/dry layer below 850 mb sampled by regional 00 UTC soundings and
noted in surface observations across northern MD, southeast PA, and
into western NJ, which may limit snowfall rates in the near term.
However, a combination of evaporative cooling and persistent
mesoscale ascent along the warm frontal zone should support adequate
low-level saturation/cooling to allow for moderate to heavy snowfall
in the coming hours.