Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 400 AM EST Mon Feb 10 2020 Valid 12Z Mon Feb 10 2020 - 12Z Thu Feb 13 2020 ...Southern California across the the southern Rockies and the southern High Plains... Days 1-2... A closed low off the northern Baja will shift east to the northern Sea of Cortez today before northern stream shortwave energy begins to weaken the system and draw it northeast from the southeastern AZ border to northern NM Tuesday night. Ongoing snow in the higher elevations of the San Gabriel, San Bernadino and San Jacinto mountains of southern CA continues through this afternoon with moderate probabilities for an additional four inches or more. Southwesterly flow ahead of the low will support expanding precipitation spreading across southern and central AZ and NM, with high elevation snows expected along the Mogollon Rim and White Mountains through tonight. Meanwhile, enhanced low level convergence/frontogenesis associated with the northern stream wave will support locally heavy snows moving south through the southern Colorado to the northern New Mexico ranges tonight into Tuesday. Areas impacted by the heaviest accumulations include the San Juan and Sangre de Cristo mountains. By early Tuesday, deepening moisture east of the Rockies will begin to interact with the low-to-mid level baroclinic zone dropping into the TX Panhandle supporting snows spreading east, with the potential for significant amounts developing across the region on Tuesday. 48 hour probabilities for 8 or more inches are moderate to high over aforementioned mountains of AZ/NM/CO as well as moderate probabilities over the southern high Plains of central NM into the TX Panhandle. ...Midwest and Northeast... Day 3... Remnant southern stream energy lifts northeast and into the northern stream trough over the Midwest Wednesday. A powerful southwesterly jet forms ahead of the northern stream trough with precip spreading across the Upper Midwest/Northeast through Wednesday night. In addition, a polar cold front shifting south across the Northern Plains and northern Great Lakes allows enhancement of the low as it tracks over the Northeast. The north side of the precip shield is cold enough for snow and a warm nose could allow light icing particularly over PA/NY Wednesday night. Currently the risk for 4 inches or more is quite low with the exception of the UP after the polar cold front across an open Lake Superior where there are 20 to 30 percent probabilities. ...Northeast... Day 1... Low pressure crosses northern Maine this afternoon. Warm air advection will allow snow to change to rain over interior New England with higher elevations seeing snow accumulation. Snow probabilities are moderate for two or more inches over the Berkshires, Green/White Mtns, and portions of interior eastern Maine. For Days 1-3, the probability of significant icing (0.25-inch or greater) is less than 10 percent. Jackson