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