Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 327 PM EST Sun Dec 27 2015 Valid 00Z Mon Dec 28 2015 - 00Z Wed Dec 30 2015 ...There is a slight risk of severe thunderstorms for parts of the Lower Mississippi Valley and Western Gulf Coast... ...Heavy snow possible from portions of the Central Plains to the Upper Great Lakes... ...There is a chance of rain/freezing rain from parts of the Southern Plains into the Great Lakes and the Northeast... ...Heavy rain possible parts of the Middle/Lower Mississippi Valley and parts of the Southeast/Southern Appalachians... A strong storm over the Southern Plains/Lower Mississippi Valley will move northward to the Great Lakes by Tuesday. Moisture from the Western Gulf of Mexico will stream northward into Lower Mississippi Valley/Southern Plains moving to the Great Lakes by Monday evening. Showers and thunderstorms will develop over the Lower Mississippi Valley into the Central Gulf Coast and the Tennessee and Ohio Valleys on Sunday evening that will move into parts of the Southeast by Monday evening/Tuesday morning. Rain will also develop over parts of Southern New England westward into parts of the Ohio Valley that will move southward into the Mid-Atlantic/Southeast by Monday afternoon. The rain will move northward by Monday evening into parts of the Great Lakes and the Ohio Valley and into parts of Southern New England by Tuesday morning. Snow will develop over the Southern High Plains moving into parts of the Central Plains/Upper Mississippi Valley by Monday evening and moving into parts of the Upper Great Lakes by Tuesday morning. Between the rain and snow, a region of rain/freezing rain will develop from parts of the Central/Southern Plains into the Great Lakes by Monday evening. Additionally, Monday evening into Tuesday morning, rain/freezing rain will develop over parts of Northern Appalachians and parts of the Northeast. In addition, snow will develop over parts of the Northeast Monday evening into Tuesday. Meanwhile, a dissipating front and associated deep upper-level trough will move into the Northwest on Sunday evening. The deep upper-level trough will move to the Southwest by Tuesday. Coastal rain and higher elevation snow will develop over the Pacific Northwest into Northern California, with the snow extending as far inland as parts of the Great Basin/Northern Intermountain Region on Sunday evening. As the trough moves inland the snow levels over Northern California will lower by Monday morning. The rain will move into Central/Southern California by Monday afternoon as snow develops over the Sierras. Snow will also move into parts of the Northern Rockies on Monday into Tuesday morning. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php