Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 332 AM EST Tue Feb 08 2022 Valid 12Z Tue Feb 08 2022 - 12Z Fri Feb 11 2022 ...New England... Day 1... An amplifying upper trough moves from the eastern Great Lakes-Ohio Valley across New England today with modest development to the coastal low off New England and heavy snow for interior NH/Maine. Strong ascent aided by left exit jet dynamics and mid level PVA along with low-to-mid level frontogenesis will continue to support a swath of moderate to locally heavy precipitation as it lifts from NH through northern Maine today. WPC probabilities are moderate for over 6" for northern Maine. ...Great Lakes... Days 1-3... A wave crosses Ontario tonight into Wednesday cold post-frontal northwesterly flow bringing lake effect snows across the western Great Lakes on Wednesday, before spreading east into the eastern Great Lakes late Wednesday into Thursday. WPC probabilities continue to show the greatest threat for accumulation of 4 inches or more centered across the western U.P. of Michigan tonight/Wednesday and then in the Tug Hill Region of Upstate New York on Wednesday night/Thursday. A stronger wave shifts southeast down the Canadian Prairies Thursday and across the northern Great Lakes Thursday night. Some residual Pacific moisture joins this developing wave to promote moderate to locally heavy snow in northern MN Thursday and over much of the western Great Lakes Thursday night with enhancements off Superior and Michigan. ...Black Hills... Day 2... A mid-level impulse embedded within progressive northwest flow along with left-exit region upper jet forcing will support snow spreading south through the northern High Plains Wednesday. For most areas, accumulations are expected to be light. However, topographical enhancement with the Black Hills will promote occasional heavy snow with Day 2 WPC probabilities moderately high for over 4", particularly on the northern slopes. The probability of significant icing is less than 10 percent Days 1-3. Jackson