View attachment 111442
Mesoscale Discussion 0095
NWS Storm Prediction Center Norman OK
0744 PM CST Fri Jan 28 2022
Areas affected...Parts of northeastern North Carolina...southeastern
Virginia...southern Maryland...Delaware...coastal New Jersey and
eastern Long Island
Concerning...Heavy snow
Valid 290144Z - 290445Z
SUMMARY...Heavy snow appears likely to develop near northern Mid
Atlantic coastal areas through late evening. This may include
increasingly sustained rates in excess of 1 inch per hour near
southern New Jersey coastal areas and eastern Long Island by around
midnight EST.
DISCUSSION...Consolidating, amplified mid-level troughing is
gradually turning east of the Mississippi Valley, and taking on a
more neutral tilt as it approaches the Appalachians. Large-scale
ascent beneath increasingly difluent flow downstream of this feature
is contributing to increasing precipitation near and offshore of Mid
Atlantic coastal areas, where a substantial cooling in mid-level
cloud tops is evident is latest satellite imagery. Through 03-06Z,
upper divergence is forecast to continue to intensify near or just
east of the northern Mid Atlantic region, as a smaller scale
perturbation begins to emerge from the base of the larger-scale
troughing. An already intensifying offshore cyclone may begin to
deepen more rapidly while continuing to migrate northward near the
Gulf Stream (east-northeast of the North Carolina coast).
On the northwestern periphery of the expanding and intensifying
precipitation shield, thermodynamic profiles are generally
sub-freezing and supportive of snow. While it appears that a
developing band of heavier snow will mostly remain offshore,
immediate coastal areas probably will be impacted. This may include
areas as far south as the Virginia/North Carolina Tidewater
vicinity, where low levels remain above freezing, but will fall
toward freezing during the next few hours in response to evaporation
of precipitation and cold advection.
With precipitable water near or in excess of .5 inches, and
lower/mid tropospheric frontogenesis likely to increase lift within
layers favorably cold for large dendritic ice crystal growth, snow
rates of 1/2 to 1+ inch per hour may become more common. It appears
that stronger mid-level frontogenetic forcing may begin to support
more sustained rates in excess of 1 inch per hour along New Jersey
coastal areas and across parts of eastern Long Island toward 05-06Z.
..Kerr.. 01/29/2022