Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 347 AM EDT Fri Apr 26 2013 Valid 12Z Fri Apr 26 2013 - 12Z Sun Apr 28 2013 ...Severe thunderstorms are possible over parts of eastern Oklahoma... ...Heavy rain possible over parts of the Lower Mississippi/Tennessee Valleys... A front over the Southern High Plains will move eastward to Tennessee Valley/Southern Plains, while becoming more east-west orientated by Saturday. Moisture from the Gulf of Mexico will stream northward overrunning the boundary producing an area of showers and thunderstorms over parts of the Central Plains that will expand eastward into the Lower Mississippi Valley by Friday evening. The showers and thunderstorms will also expand southwestward along the front into the Southern Plains while continuing to expand eastward into the Central Gulf Coast by Saturday evening. In addition, an area of rain will develop over parts of the Central Plains/Middle Mississippi Valley moving eastward to the Tennessee Valley on Saturday, while becoming light to moderate in intensity. In the meantime, a weakening warm front over the Upper Mississippi Valley/Upper Great Lakes will dissipate by Friday night. Associated light rain will develop over parts of the Upper Great Lakes on Friday. Furthermore on Saturday, a front will approach the Pacific Northwest and move inland to the Northern Intermountain Region by Saturday evening. Rain will develop with the front over parts of the area Saturday morning into Saturday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php