Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 414 PM EDT Sun Mar 19 2017 Valid 00Z Mon Mar 20 2017 - 00Z Wed Mar 22 2017 ...Moderate to heavy snow possible over the Sierras... ...Heavy rain over parts of Northern California... A wave of low pressure over the Central Plains will move eastward to the Mid-Atlantic Coast by Tuesday. Rain will develop overnight Sunday over parts of the Upper Mississippi Valley/Upper Great Lakes that will move into parts of the Lower Great Lakes by Monday evening and into parts of the Northern Appalachians by Tuesday morning. Showers and thunderstorms will develop over parts of the Western Ohio Valley by early Monday morning that will move to parts of the Tennessee Valley and the Central/Southern Appalachians as well as parts of the Southern Mid-Atlantic by Tuesday. Overnight Monday, rain will develop over parts of the Northern Mid-Atlantic into Tuesday. A lingering front extending from parts of Northern California to the Northern High Plains/Central Rockies will be mainly stationary over the region through Tuesday. In addition, a plume of moisture from the Pacific will move into parts of Northern California that will move into Central California by Tuesday morning. Rain and highest elevation snow will develop from parts of Northern California/Pacific Northwest to the Northern High Plains through Monday morning and into Tuesday. On Monday, rain will expand into parts of Central California and into Southern California by Tuesday. Overnight Monday, snow will develop over the Sierras into Tuesday. Also by Tuesday morning, rain and snow will develop over parts of the Northern/Central Plains. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php