Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 429 PM EDT Tue Sep 20 2016 Valid 00Z Wed Sep 21 2016 - 00Z Fri Sep 23 2016 ...There is a slight risk of severe thunderstorms over parts of the Upper Mississippi Valley... ...Heavy rain possible over parts of the Upper Mississippi Valley... ...Heavy rain possible over parts of the Southern Mid-Atlantic Coast... ...Heavy rain possible over parts of the Northern High Plains and parts of the Great Basin... An upper-level low over the Southern Mid-Atlantic/Southeast Coast will be quasi-stationary through Thursday. The system will develop showers and thunderstorms from parts of the Mid-Atlantic Coast to the Southeast Coast, likewise, through Thursday. Meanwhile, moisture associated with Tropical Storm Paine will move inland over parts of Southern California into parts of the Southwest and eastward to parts of the Southern/Central Rockies. The storm will produce showers and thunderstorms over parts of the Southern California into parts of the Southwest moving into parts of the Southern/Central Rockies overnight Tuesday. The showers and thunderstorm will end over parts of Southern California by Wednesday evening and winding down over the Southern/Central Rockies by Thursday morning. In the meantime, a front extending from the Western Ohio Valley westward to parts of the Great Basin will have moisture from the Western Gulf of Mexico will stream northward over the Plains will begin to produce showers and thunderstorm over parts of the Upper Mississippi Valley to parts of the Northern Rockies. By Wednesday morning, moisture from Tropical Storm Paine will cross the Rockies and move into the Central Plains into the Upper Mississippi Valley. With the added moisture, showers and thunderstorms will continue over the Upper Mississippi Valley into the Northern Rockies through Thursday. The showers and thunderstorms will move into the Upper Great Lakes Wednesday afternoon into Thursday. In addition, an upper-level low over the Pacific Northwest will deepen and expand into Central California. The energy will produce showers and thunderstorms over parts of Central California into parts of the Great Basin/Northern Rockies starting Wednesday afternoon expanding into parts of Northern California/Pacific Northwest and into parts of the Northern/Central Rockies by Thursday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php