Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 419 PM EDT Sat Apr 14 2018 Valid 00Z Sun Apr 15 2018 - 00Z Tue Apr 17 2018 ...There is a slight risk of severe thunderstorms over parts of the Southeast/Tennessee Valley... ...Heavy snow possible over the Upper Great Lakes... ...Rain/freezing rain possible from the Great Lakes eastward to the Northeast... ...Heavy rain possible from parts of the Northeast/Mid-Atlantic to parts of the Tennessee Valley... A deep storm over the Middle Mississippi/Western Ohio Valleys will slowly move northeastward to the Upper Great Lakes by Monday. The system will produce snow over parts of the Central Plains and Middle/Upper Mississippi Valley into the Upper Great Lakes and parts of Northern New England that will end over the Central Plains and parts of Northern New England by Sunday evening. The snow will move into parts of the Ohio Valley overnight Sunday while continuing over parts of the Upper/Middle Mississippi Valley and the Upper Great Lakes through Monday. In addition, a region of rain/freezing rain will develop over parts of the Great Lakes into Northern New England that will end overnight for the Great Lakes while continuing over parts of Northern New England into Monday. Furthermore, showers and thunderstorms will develop along and ahead of the associated front from parts of the Western Ohio Valley southward to the Lower Mississippi Valley that will retreat to the Southeast overnight Saturday only to expand northward into the Southern Mid-Atlantic by Sunday afternoon. The showers and thunderstorms will move off the Southeast/Southern Mid-Atlantic Coast overnight Sunday. Areas of rain will also develop over parts of the Ohio Valleys to Southern New England on Saturday evening that will continue through Monday morning. Meanwhile, a front along the Pacific Northwest Coast will slowly move inland to the Northern Rockies/Great Basin into parts of Southern California by Monday. The system will produce rain over parts of the Pacific Northwest and higher elevation snow/lower elevation rain over parts of the Northern Rockies on Saturday evening. The snow levels will lower as the boundary moves inland. Rain will begin to move over parts of Northern California by Sunday morning as the higher elevations of the Pacific Northwest will change over to snow. By Sunday evening, rain will move into parts of Central California as snow develops over the higher elevations of Northern California. Overnight Sunday snow will expand into parts of the Great Basin and the Sierras while coastal rain continues over the Pacific Northwest and Northern/Central California Coast. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php