Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 429 PM EDT Sat Apr 15 2017 Valid 00Z Sun Apr 16 2017 - 00Z Tue Apr 18 2017 ...There is a slight risk of severe thunderstorms from Southern/Central Plains to parts of the Middle Missouri Valley/Middle Mississippi Valley... ...Heavy rain possible over parts of eastern Oklahoma... A front extending from the Upper Great Lakes to the Southern High Plains will move eastward to off the Northeast Coast while extending westward from the Mid-Atlantic to Southern High Plains by Monday. Showers and thunderstorm will develop along and ahead of the boundary from the Upper Great Lakes/Upper Mississippi Valley to the Southern Plains that will move to the Northeast Coast by overnight Sunday. In addition, the showers and thunderstorms will extend from parts of the Mid-Atlantic to the Southern Plains through Monday. Additionally, showers and thunderstorms will develop along the associated warm front extending from the Great Lakes to the Mid-Atlantic that will lift northeastward off New England Coast by Sunday morning. Rain and snow will develop over parts of Maine overnight Sunday into Monday morning. Meanwhile, upper-level energy over parts of the Pacific Northwest to the Northern Plains will aid in producing daytime showers over the region through to early Saturday evening. By Sunday afternoon, a weakening front approaching the California Coast along with an associated plume of moisture will move into parts of Central/Northern California. The system will produce rain and higher elevation snow over parts of Northern/Central California on Sunday afternoon into evening and into Monday, too. The rain and higher elevation snow will move into parts of the Pacific Northwest overnight Sunday with snow and lower elevation rain developing over parts of the Northern Rockies by Monday. Elsewhere, a weak boundary passing over parts of the Upper Mississippi Valley/Upper Great Lakes will produce rain over parts of the area Sunday evening into Monday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php