Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 418 AM EST Sat Mar 05 2022 Valid 12Z Sat Mar 05 2022 - 12Z Tue Mar 08 2022 ...Western U.S.... Days 1-2... An upper low will continue to drop southeast across California into southern Nevada today before pivoting east toward the Four Corners region tonight into early Sunday. This will support high elevation snows from the California mountains through the Great Basin and portions of the Southwest into the central Rockies. Some of the heaviest accumulations are expected to occur across the mountains of central Nevada, where low-to-mid level frontogenesis along with favorable upper forcing is expected to support widespread totals of 4 to 8 inches, with local accumulations of a foot or more across the region. This low is forecast to transition to an open wave and move east of the Rockies into the High Plains, but not before producing at least some light to moderate snow accumulations across the central Rockies on Sunday. Meanwhile, a northern stream shortwave dropping south from western Canada is expected to produce some light to moderate snow accumulations across the northern Rockies late Sunday into early Monday. ...Central Plains and Upper Midwest through the Great Lakes/New England... Day 1... Precipitation associated with a low-amplitude shortwave lifting northeast from the central Plains will continue to develop this morning across the Upper Midwest, producing an initial round of snow and ice across portions of eastern Minnesota, northern Wisconsin, and northern Michigan. Some areas of northern Wisconsin and Upper Michigan may see ice accumulations of 0.10 inch or more before this initial wave moves out by the afternoon. Meanwhile, a more defined upstream wave will continue to lift northeast across the Rockies and into the central High Plains this morning. Northeasterly flow on the backside of a 700 mb low tracking northeast across western Nebraska, overlapped by favorable upper jet forcing, will support snow shifting east this morning from the southeastern Wyoming and northeastern Colorado ranges into the Nebraska Panhandle and southeastern South Dakota later this morning. This next system will continue to amplify as it moves from the central Plains into the Upper Midwest this evening. A favorable upper jet couplet overlapping low-to-mid level frontogenesis will support the development of moderate to heavy precipitation. Thermal profiles continue to indicate a wintry mix is likely, with significant ice accumulations across portions of southwestern to central Minnesota, northern Wisconsin, and Upper Michigan. This will likely bring 24 hour ice accumulations upward over a 0.25 inch in some locations. Farther to the east, warm advection precipitation falling out ahead of the system is expected to fall as a wintry mix, resulting in light snow and ice accumulations across portions of northern New York and New England tonight into early Sunday. ...Central Plains to the Northeast... Days 2-3... The shortwave moving into the southern High Plains Sunday night will be stretched northeastward through the central Plains and mid Mississippi Valley, ahead of an amplifying northern stream trough over the northern Plains and Upper Midwest. Favorable upper jet forcing and strong frontogenesis will support precipitation blossoming from the mid Mississippi Valley into the Great Lakes and Ohio Valley Sunday night, and into the Northeast on Monday. Along the northern edge of the precipitation shield, thermal profiles suggest frozen precipitation is likely. Confidence in the details is quite limited at this point, however at least some light snow accumulations appear likely from the mid Mississippi Valley to Lower Michigan, northern New York, and New England. Pereira