Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 406 PM EDT Wed May 10 2017 Valid 00Z Thu May 11 2017 - 00Z Sat May 13 2017 ...There is a slight risk of severe thunderstorms from parts of the Ohio Valley to the Central/Southern Plains... ...Heavy rain possible over parts of the Middle/Lower Mississippi Valley and parts of the Central Plains... ...Heavy rain possible over parts of the Central Appalachians and the Southern Mid-Atlantic... An east-west orientated front extending from the Southern Mid-Atlantic westward to the Central Plains will be quasi-stationary along the eastern portion while the western portion moves southeastward to the Lower Mississippi Valley on Thursday evening into Friday. Additionally, a wave of low pressure over the Middle Mississippi Valley will advance along the boundary to the North Carolina Coast by Friday. Moisture from the Western Gulf of Mexico will stream northward and overrun the front that will aid in the development of showers and thunderstorms from the Central Plains eastward to the Ohio Valley that will expand into the Central Appalachians/Southern Mid-Atlantic overnight Wednesday. The showers and thunderstorms will continue along the boundary from the Southern Mid-Atlantic to the Middle Mississippi Valley through Friday. In addition, rain will develop over parts of the Upper Great Lakes on Wednesday evening that will move eastward to the Lower Great Lakes and the Northern Mid-Atlantic by Thursday afternoon into Friday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php