Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 259 PM EST Thu Dec 12 2019 Valid 00Z Fri Dec 13 2019 - 00Z Sun Dec 15 2019 ...Heavy snow in the mountains of the Pacific Northwest and Intermountain West... ...Periods of snow over to develop over the Upper Midwest and Upper Great Lakes... ...Widespread showers across the Southeast and rain/freezing rain in the Central Appalachians on Friday... A stream of Pacific moisture accompanied by several Pacific disturbances will "Let It Snow" across the Cascades, Sierra Nevada, and the northern and central Rockies the next today and into the weekend. Snow totals will be heavy in the highest elevations with snow being measured in feet in parts of these mountain ranges. The NWS has issued Winter Storm Warnings and Winter Weather Advisories across the higher elevations of the West that will last into the weekend. As an upper-level trough dives south into the the South Central U.S. tonight, a surface low pressure system will strengthen in the Gulf of Mexico. This storm will tap into Gulf of Mexico and Atlantic moisture causing showers to increase in coverage tonight and eventually overspread the Southeast by Friday morning. Severe weather is also possible across northern Florida, southern Georgia, and southern South Carolina Friday afternoon. Further north, sub-freezing temperatures in the southern and central Appalachians will set the stage for areas of freezing rain. In preparation for potentially icy conditions Friday morning and early afternoon, the NWS has issued Winter Weather Advisories from western North Carolina to the Appalachians bordering the Mason-Dixon line. The storm will strengthen and track up the Eastern Seaboard Friday night and reach the Northeast on Saturday. Rain will be the primary precipitation type across much of the Northeast. The lone exception to this is northern New England where precipitation will start out as snow before changing over to a wintry mix Friday night and then to all rain during the day Saturday. Areas along and east of I-95 will average 1-1.5". Lake effect snow showers will form down winds of the Lakes as cold temperatures and brisk northwest winds develop. Some accumulating snowfall is likely with locally heavy amounts possible/ Mullinax Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php