Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 401 PM EDT Fri Aug 29 2014 Valid 00Z Sat Aug 30 2014 - 00Z Mon Sep 01 2014 ...Heavy rain possible for portions of the Lower Mississippi Valley and Tennessee Valley... Low pressure over the Upper Mississippi Valley will move northeastward to Southeastern Ontario by Sunday. Moisture from the Gulf of Mexico will pool along the associated front aiding in producing showers and thunderstorms from the Upper/Middle Mississippi and Upper Great Lakes that will move slowly to the Lower Great Lakes/Northeast by Sunday. In addition, light to moderate rain will develop over parts of Northern New England on Sunday morning. Meanwhile, upper-level energy over the Central Gulf Coast will lift northeastward to the Ohio Valley by Sunday morning. Moisture rich air from the Gulf of Mexico will invade the Lower Mississippi Valley and move northeastward to the Ohio Valley/Lower Great Lakes by Sunday. The Moisture, upper-level energy, and upper-level jet dynamics will aid in producing showers and thunderstorms over the Western/Central Gulf Coast on Friday evening and expand northward up the Lower Mississippi Valley with moderate rain by Saturday morning. The area of showers and thunderstorms, with moderate rain, will extend from the Ohio Valley/Lower Great Lakes to parts of the Tennessee Valley/Lower Mississippi Valley by Sunday morning. Additionally, easterly flow off the Atlantic will aid in producing showers and thunderstorms over Florida and the Southeast Coast through Sunday. An upper-level trough over the Eastern Pacific will move inland to the Rockies by Sunday. The associated front will develop over the Northern Rockies and move eastward to the Northern Plains and southward to the Great Basin/Central Rockies. Showers and thunderstorms will develop along the boundary on Saturday morning over the Northern Rockies/Northern High Plains that will move to the Upper Mississippi Valley by Sunday. Showers and thunderstorms continue over parts of the Northern/Central Rockies Saturday evening into Sunday morning. Furthermore, showers and thunderstorms will develop over parts of the Central Rockies on Friday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php