Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 AM EDT Sat May 19 2018 Valid 12Z Sat May 19 2018 - 12Z Mon May 21 2018 ...There is a slight risk of severe thunderstorms over parts of the Southern High/Central Plains into parts of the Middle Mississippi Valley... ...Heavy rain possible over parts of the Southern Plains into the Middle Mississippi Valley... ...Heavy rain possible over parts of Florida to parts of the Southern Mid-Atlantic... ..Temperatures will be 10 to 25 degrees below average over parts of the Central Plains... Weakening upper-level energy over the Ohio Valley will lift northeastward into New England by Sunday merging with stronger upper-level energy moving over Southeastern Canada Sunday evening into Monday. A plume of moisture extending from Florida northward to the Northern Appalachians into parts of the Great Lakes will continue over most of the East Coast through Monday. The moisture and energy will aid in producing rain and thunderstorms over parts of the Great Lakes/Ohio Valley into the Mid-Atlantic into parts of the Southeast that will move into Northern New England by Sunday morning. The rain and thunderstorms continue over parts of the Mid-Atlantic/Lower Great Lakes through Sunday morning. The rain and embedded thunderstorms will move off the Northeast/Northern Mid-Atlantic Coast overnight Sunday. While the showers and thunderstorms will continue over the Southern Mid-Atlantic into the Southeast through Sunday evening into Monday. Another area of upper-level energy over the Central Plains will slowly move eastward to parts of the Middle Mississippi Valley by Sunday night. The energy will interact with moisture over the Plains and the Mississippi Valley to produce showers and thunderstorms over parts of the Northern/Central Rockies into parts of the Central Plains that will expand into parts of the Southern Plains by Saturday evening. By Sunday morning, the showers and thunderstorms will extend from parts of the Middle Mississippi/Western Ohio Valleys into the Southern Plains that will expand into the Ohio/Tennessee Valleys and parts of the Central/Southern Appalachians into parts of the Eastern Gulf Coast by Sunday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php