Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 359 AM EDT Wed May 25 2016 Valid 12Z Wed May 25 2016 - 12Z Fri May 27 2016 ...There is a slight risk of severe thunderstorms from the Southern Plains to the Upper/Middle Mississippi Valley and parts of the Central/Northern Plains... ...Heavy rain possible over parts of the Southern Plains... ...Heavy rain possible over parts of the Central Plains/Middle Mississippi Valley... A deep upper-level trough over the western third of the country will move eastward to the Plains/Rockies by Thursday evening. Downstream from the upper-level trough, moisture from the Gulf of Mexico will stream northward over the Southern Plains into the Middle Mississippi Valley and the Upper Midwest will extend into the Great Lakes/Ohio Valley by Thursday evening. Showers and thunderstorms will develop over parts of the Plains and the Mississippi Valley will expand into parts of the Great Lakes/Ohio Valley by Wednesday evening. By Thursday morning, the showers and thunderstorms will develop over parts of the Upper Mississippi Valley/Upper Great Lakes southwestward into the Southern Plains and over the Great Lakes/Ohio Valley will expand eastward into parts of the Northern/Central Appalachians by Thursday evening. Under the upper-level trough showers and thunderstorms will develop from parts of California to the Northern Intermountain Region/Great Basin and the Northern/Central Rockies by Wednesday evening with daytime heating contributing to the areal extend of the storms. On Thursday, the showers and thunderstorms will extend from the Northern/Central High Plains to the Great Basin/Northern Intermountain Region with daytime heating contributing to the areal extend. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php