Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 350 AM EDT Sun Apr 22 2018 Valid 12Z Sun Apr 22 2018 - 12Z Tue Apr 24 2018 ...Heavy rain possible from parts of the Ohio/Tennessee Valleys into the Southern Mid-Atlantic/Southeast... ...Heavy snow possible over parts of the Northern Rockies/Northern High Plains... A storm over the Lower Mississippi Valley will slowly move into the Tennessee Valley/Southeast by Monday evening. Showers and thunderstorms will develop along and ahead of the associated front over the Lower Mississippi Valley that will move eastward to the Southeast Coast into the Tennessee Valley by Monday evening into Tuesday. Rain will also develop over parts of the Middle Mississippi Valley into parts of the Tennessee Valley that will expand into parts of the Ohio Valley/Southern Appalachians and parts of the Southern Mid-Atlantic by Sunday evening. The rain will expand into parts of the Central Appalachians and the Mid-Atlantic by Monday evening. Meanwhile, upper-level energy over the Pacific Northwest will move eastward to the Northern Rockies/Northern High Plains by Monday evening into Tuesday. The energy will produce rain and higher elevation snow over parts of the Northern/Central Rockies overnight Sunday that will expand into parts of the Northern/Central High Plains by Monday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php