Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 337 PM EST Sun Nov 27 2016 Valid 00Z Mon Nov 28 2016 - 00Z Wed Nov 30 2016 ...There is a slight to enhanced risk of severe thunderstorm over the Lower Mississippi Valley on Monday... ...Heavy rain possible over parts of the Western Ohio, Tennessee, and Lower/Middle Mississippi Valleys.... ...Heavy precipitation possible over the Cascades and Sierras... ...Snow possible over parts of the Rockies into Great Basin and Northern Plains... A front extending from the Northern to Southern Plains will move eastward to the Great Lakes and Ohio Valley by Tuesday morning. Showers and thunderstorms will develop along and ahead of the boundary from the Central Plains to the Southern Plains that will move eastward to the Central/Southern Appalachians and parts of the Southeast/Central Gulf Coast by Tuesday. Some of these thunderstorms will be severe over the Lower Mississippi Valley on Monday, see the Storm Prediction Center for more details about the hazards associated with these storms. In addition, rain will develop over parts of the Northern Plains into parts of the Middle Mississippi Valley that will expand into the Upper Mississippi Valley and Upper Great Lakes into parts of the Western Ohio Valley overnight Sunday into Monday morning. By Tuesday morning, the rain will extend from parts of the Northern Plains into the Great Lakes/Mid-Atlantic and parts of the Northeast. Snow will also develop on the northwest side of the precipitation shield over the Northern/Central Plains overnight Sunday into Monday morning and continuing through Tuesday. Additionally, upper-level energy over the Southwest/Great Basin will move roughly northeastward to the Great Lakes by Monday night/Tuesday. The upper-level energy will produce snow over the Northern/Central Rockies into the Great Basin and the Southwest with rain at lower elevations and Southeastern California on Sunday evening. The snow and lower elevation rain will move into the Central/Southern Rockies by Monday morning, retreating into the Central Plains by Monday afternoon. A second front moving onshore over the Northwest will move southeastward to Southern Plains while extending westward into parts of the Southwest by Tuesday. The system will produce rain and higher elevation snow over the Pacific Northwest and into parts of Northern California by Sunday evening. Snow will expand eastward overnight Sunday into the Great Basin and parts of the Northern/Central Rockies by Monday morning. The snow will expand into parts of the Southwest/Southern Rockies by Monday evening then taper off to snow showers over parts of the Rockies and the Great Basin/Southwest by Tuesday. Furthermore, rain and higher elevation snow will move into parts of Northern/Central California by Monday morning. The rain and higher elevation snow will begin to wind down by Monday evening over California and overnight Monday into Tuesday over the Northwest. Meanwhile, easterly flow off the Atlantic will aid in producing rain showers over the southeastern portion of Florida through Tuesday . Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php