MD 1968 CONCERNING HEAVY SNOW FOR PARTS OF WESTERN/NORTHERN NEW YORK
Mesoscale Discussion 1968
NWS Storm Prediction Center Norman OK
0640 AM CST Sun Nov 20 2022
Areas affected...Parts of western/northern New York
Concerning...Heavy snow
Valid 201240Z - 201815Z
SUMMARY...A heavy lake-enhanced snow band will likely persist
through the day, with rates of 3-4 inches per hour possible closer
to the lake, and 1-2 inches per hour possible farther east into
parts of the Mohawk Valley by late morning.
DISCUSSION...An ongoing lake-enhanced snow band over Lake Ontario
and adjacent portions of western/northern New York is expected to
undergo some reorientation through the day today, with low-midlevel
flow gradually veering to more of a west to west-northwesterly
direction with time as the deep longwave trough over the region
shifts eastward. Steep tropospheric lapse rates and very cold
temperatures aloft (-15 C at 850 mb and -27 C at 700 mb on 12Z BUF
sounding) will continue to support sufficient instability for the
maintenance of locally intense snow rates of 3+ inches per hour. As
the band takes on a more west-northwest to east-southeast
orientation, the heaviest snow is expected to shift gradually
southward across parts of Oswego, southern Lewis, and northern
Oneida Counties. Favorable instability and surface convergence could
also support localized rates of 1-2 inches per hour along the
eastward extension of the snow band into parts of the Mohawk Valley
by late morning.
In addition to the heavy snow rates, increasing low-level flow will
support strong winds (with gusts in the 30-45 mph range), which will
exacerbate low-visibility concerns in areas that experience the
heavier snow rates.
..Dean.. 11/20/2022
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ALY...BGM...BUF...
LAT...LON 43587696 43647585 43587511 43367473 43127453 42927461
43047605 43207710 43457728 43587696
