Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 420 PM EDT Sat Apr 18 2015 Valid 00Z Sun Apr 19 2015 - 00Z Tue Apr 21 2015 ...There is a slight risk of severe thunderstorms over parts of the Central/Southern Plains... ...Heavy rain possible from parts of the Mid-Atlantic southwestward to Central Gulf Coast... An upper-level low over the Central High Plains will move to the Ohio Valley and get in lockstep with upper-level energy over South-Central Canada by Monday. Moisture from the Gulf of Mexico will move into the Ohio Valley then into the Mid-Atlantic by Monday. Showers and thunderstorms will develop over parts of the Central/Southern Plains into the Middle Mississippi Valley/Central Gulf Coast and the Southeast on Saturday evening. The showers and thunderstorms will move into the Mid-Atlantic to the Southeast and over parts of the Ohio/Tennessee Valleys/Southern Appalachians by Monday. In addition, the storm will produce snow over parts of the Central Rockies through Sunday morning with pockets of snow lingering over parts of the Central Rockies Sunday evening into Monday morning. Rain will also develop over the Northern Plains and slowly move eastward to the Great Lakes/Northern Ohio Valley by Monday. Another area of rain will develop over parts of the Mid-Atlantic on Sunday evening and move into the Northeast by Monday morning. Elsewhere, low pressure over Southern New England Coast will move eastward out over the Atlantic by early Sunday morning. The low will produce rain over parts of New England on Saturday evening, ending with rain and snow by late Saturday night. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php