Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 241 AM EST Sun Dec 01 2024 Valid 12Z Sun Dec 01 2024 - 12Z Tue Dec 03 2024 ...Heavy lake-effect snow starts to wind down over the Upper Great Lakes later on Sunday... ...Heavy lake-effect snow continues downwind from Lake Erie through Tuesday... ...Light to moderate snow over parts of the Northern Plains and Upper/Middle Mississippi Valley and Central Appalachians on Sunday; on Monday, light to moderate snow over parts of the Southern Ohio Valley... ...Temperatures will be 10 to 15 degrees below average over parts of the Northern Plains to the Ohio Valley and the eastern third of the country... High pressure over Central Canada will settle southeastward to the Middle Mississippi Valley by Tuesday. The high pressure will also usher cold air over parts of the Northern Plains to the Ohio Valley and across the eastern third of the country, bringing temperatures of 10 to 15 degrees below average. Freeze Warning will be over the Central/Eastern Gulf Coast States. The upper-level troughing over the Upper Midwest/Upper Great Lakes into the Northeast will weaken Monday into Tuesday. The cold air streaming over the Great Lakes will produce heavy lake-effect snow over the Upper Peninsula of Michigan through Monday morning. Lighter snowfall will develop over most of the west coast of the Lower Peninsula of Michigan. However, heavy lake-effect snow will develop over the parts of the northern Lower Peninsula of Michigan near the Traverse City to Gaylord regions and will start to taper off on Monday into Tuesday. Moreover, heavy lake-effect snow will continue downwind from Lakes Erie through Tuesday. The heavy lake-effect snow will continue downwind of Lakes Ontario on Sunday and taper off on Monday into Tuesday. Moreover, upper-level energy will produce light to moderate snow over parts of the Northern Plains and Upper/Middle Mississippi Valley on Sunday. Furthermore, a wave of low pressure will create light to moderate snow over parts of the Central Appalachians on Sunday. On Monday, a second wave of low pressure will create light snow over parts of the Southern Ohio Valley into the Tennessee Valley. A third wave of low pressure over West-Central Canada will initiate light snow over parts of the Upper Midwest by Tuesday morning. Meanwhile, weak return flow off the Gulf of Mexico will create light rain over parts of the Western Gulf Coast on Sunday and scattered showers and thunderstorms on Monday. Elsewhere, upper-level ridging over parts of the West Coast will create stagnant air conditions over the valley locations from interior California into the Pacific Northwest, leading to areas of dense fog and poor air quality. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php