Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 234 PM EST Tue Dec 22 2020 Valid 00Z Wed Dec 23 2020 - 00Z Fri Dec 25 2020 ...Snow and gusty winds likely across the Northern Plains and Upper Great Lakes through early Thursday... ...Threat of damaging wind gusts and heavy rain shifts toward the eastern third of the country by late Christmas Eve... A surface low pressure system currently moving across the northern High Plains is forecast to track eastward into the Upper Midwest on Wednesday, spreading a variety of weather and hazards to the central CONUS. First, snow is likely across the northern Plains tonight, with higher elevations of the Northern/Central Rockies experiencing a few inches of snow as well. Winds are expected to ramp up this evening as the surface low continues to strengthen. High Wind Watches and Warnings are in place across much of the northern and central High Plains. Also on Wednesday, snow is likely on the backside of the low pressure system for the Upper Midwest and Upper Great Lakes region. Accumulations of several inches are expected for northern Minnesota, Wisconsin, and the Upper Peninsula of Michigan through Thursday morning. Snow combined with gusty winds could lead to lowering visibility and thus potentially treacherous travel conditions. Farther south, moisture from the Gulf of Mexico will increase on Wednesday, leading to rain and thunderstorms ahead of the strong cold front associated with the low pressure system. Rainfall totals of over an inch are expected for portions of the Lower Mississippi Valley into the Tennessee Valley through Thursday morning, with strong thunderstorms possible as well. By Thursday evening, strong winds and heavy rain are expected to enter the central Appalachians and Northeast. This rainfall on top of an abundance of fresh snow could lead to flooding concerns across the region. Another concern is the added weight that rain will put on top of homes and buildings where over a foot of snow still lies. In terms of temperatures, the strong cold front will bring much below average temperatures to the central U.S. and Rockies on Wednesday. Meanwhile, much warmer than average temperatures (by 15 to 30 degrees) are likely into the Ohio Valley, Great Lakes, and East Coast through Thursday. These warm temperatures throughout the Northeast will help increase the flooding threat as fresh snowpack melts into nearby streams and rivers. Elsewhere, with warm and dry conditions over the next couple days in the Southern High Plains, elevated risks of fire weather are in place there. Additionally, fire weather conditions could become critical over portions of Southern California on Wednesday. Tate/Snell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php