Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 416 PM EDT Sun Oct 13 2024 Valid 00Z Mon Oct 14 2024 - 00Z Thu Oct 17 2024 ...Northeast... Days 1-3... A potent trough crosses the Great Lakes tonight and spins into a closed low over Maine on Monday. This low stalls as a reinforcing trough dives over the Upper Midwest Monday night before digging through the southern Appalachians through Tuesday night. Troughing then extends down the length of the Eastern Seaboard Wednesday. Snow levels drop below 3000ft over Northeastern terrain such as the Adirondacks, Greens, and Whites through Monday on the back side of the developing low. Snow levels then remain around 2000ft across most of NY and New England through Wednesday. Several inches of snow will fall in occasional precip through these terrain areas with 72hr totals over 6" most likely above about 4000ft in the Adirondacks, Greens, and Whites. ...Northwest... Day 3... A deep low currently in the Gulf of Alaska dislodges southeast Tuesday night and a reinforcing upper trough rounds the low and pushes over the Pacific Northwest on Wednesday. Strong moisture advection ahead of this trough allows at least moderate precip rates and the height falls on Wednesday allow snow levels to drop to around 5000ft over the Washington Cascades by Wednesday afternoon. Heavy snow is expected in the highest Cascades with accumulating snow reaching the higher level WA passes by 00Z Thursday. The probability of significant ice across the CONUS is less than 10 percent. Jackson