Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 253 AM EST Sun Dec 1 2019 Valid 12Z Sun Dec 1 2019 - 12Z Tue Dec 3 2019 ...Big winter storm continues to cause havoc for Thanksgiving holiday travelers... The trans-continental storm system that has hammered the western U.S. and northern Plains with heavy snow and strong winds has now reached the Great Lakes region. This multi-faceted storm is producing a variety of impactful weather conditions on a busy holiday travel weekend, ranging from blizzard conditions over parts of the Upper Midwest to strong thunderstorms across the Southeast U.S. Heavy snow can be expected from the eastern Dakotas to northern Michigan on Sunday, with potential snowfall accumulations on the order of 6 to 12 inches. By late Sunday, secondary cyclogenesis occurs off the southern New England coast and becomes the dominant low pressure center through early in the week. This will evolve into more of a typical nor'easter type system with rain and wind near the coast, and heavy snow inland. The potential exists for 8 to 16 inches of snow across interior portions of New York and extending eastward to southern Maine, with winter storm warnings in effect. Farther to the south across the central Appalachians, freezing rain will be more of a problem with the potential of up to a quarter inch of ice accretion from extreme western Maryland to central Pennsylvania where ice storm warnings are in effect. Severe travel disruptions are likely for many of these areas. Across the West Coast, a slow moving storm over the eastern Pacific will have an influence across California and into Oregon as a plume of moisture advects inland. Periods of rain and heavy snow across the Sierra Nevada can be expected through the remainder of the weekend, adding to the heavy precipitation that has been observed last week. Lighter snow will likely reach farther east across the Intermountain West on Sunday. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php