MD 1966 CONCERNING HEAVY SNOW FOR PORTIONS OF FAR WESTERN NEW YORK INTO EXTREME NORTHWEST PENNSYLVANIA AND EXTREME NORTHEAST OHIO
Mesoscale Discussion 1966
NWS Storm Prediction Center Norman OK
0725 PM CST Sat Nov 19 2022
Areas affected...Portions of far western New York into extreme
northwest Pennsylvania and extreme northeast Ohio
Concerning...Heavy snow
Valid 200125Z - 200730Z
SUMMARY...A heavy snow band should move off of lake Erie in the next
couple of hours, supporting 2-3 inch/hr snowfall rates for areas
east of the shoreline. Near-zero visibility is possible at times,
with travel conditions also expected to become dangerous.
DISCUSSION...An upper trough and associated surface lee trough/cold
front is moving eastward across the Great Lakes/Ontario region and
should progress across Lake Erie soon. Convergence along the cold
front is already supporting intensification of a pre-existing band
of snow over Lake Erie, and this band should shunt eastward with the
passage of the cold front. As this occurs, strong low-level
convergence and subsequent rapid uplift of a low-level buoyant
airmass, characterized by 8-9 C/km low-level lapse rates (per last
few mesoanalysis runs), will support an appreciable fetch of
moisture before and during the time the snow band moves ashore.
2-3 inch/hr snowfall rates are likely in association with the band.
While the band may not progress as rapidly inland as a snow squall,
rapid decreases in visibility along with gusty winds are likely,
promoting dangerous travel conditions. High-resolution deterministic
and ensemble guidance also suggests heavy snow moving ashore around
02-03Z (9-10 PM EST) and peaking around 06Z (after midnight EST).
..Squitieri.. 11/20/2022
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BUF...CTP...PBZ...CLE...
LAT...LON 43217892 43337852 43357815 43287787 43117775 42807766
42307792 41867838 41467923 41278029 41278099 41398142
41578146 41758119 42008049 42297977 42597920 42777898
42977900 43087896 43217892
