MD 1967 CONCERNING HEAVY SNOW FOR PORTIONS OF NORTHWESTERN NEW YORK
Mesoscale Discussion 1967 NWS Storm Prediction Center Norman OK 1232 AM CST Sun Nov 20 2022 Areas affected...portions of northwestern New York Concerning...Heavy snow Valid 200632Z - 201200Z SUMMARY...Heavy snow is expected to become gradually more common as a primary snow band begins to overspread more inland areas. At least 2-3 inch/hr snowfall rates are possible. The heavy snow will peak in the 08-12Z/3-7 AM EST time frame. DISCUSSION...Mainly light to moderate snow has been falling across Jefferson into western St. Lawrence Counties in Upstate NY over the past several hours. However, as the upper trough and associated 700 mb cold-air advection begins to overspread the northern Hudson Valley, low-level lapse rates will further steepen into the 7-8 C/km range while deep-layer ascent also increases. Latest KTYX radar data suggests that the primary snow band emanating off of Lake Ontario is already undergoing intensification and this trend should continue through the remainder of the night. 2-3 inch/hr snowfall rates are possible in the more intense portions of the band, mainly from northern Lewis County over the next few hours, and then points farther south closer to sunrise. An instance or two of 4 inch/hr snowfall rates cannot be ruled out. In addition, reduced visibility and dangerous travel conditions are expected to accompany the more intense portions of the snow band. ..Squitieri.. 11/20/2022 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BTV...ALY...BGM...BUF... LAT...LON 43557636 43967612 44387583 44547547 44477524 44237509 43897510 43547521 43377537 43287556 43337605 43557636