Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 257 AM EDT Sun May 24 2015 Valid 12Z Sun May 24 2015 - 12Z Tue May 26 2015 ...Heavy rain possible over parts of the Southern Plains/Lower Mississippi Valley and parts of the Upper Mississippi Valley... ...There is a slight risk of severe thunderstorms for parts of the Lower/Middle Mississippi Valley and a portion of the Southern Plains... ...Temperatures will be 10 to 15 degrees below average over the Rockies... A storm over the Central High Plains will slowly move northeastward to the Upper Mississippi Valley by Monday evening. Moisture from the Western Gulf of Mexico will flow northward over the Plains into the Mississippi Valley that will move eastward to the Central Gulf Coast into the Great Lakes before a new plume of moisture begins to move over the Southern Plains by Monday evening. Showers and thunderstorms will develop over the most of the Plains and into parts of the Mississippi Valley, on Sunday, that will expand into parts of the Central Gulf Coast to the Ohio Valley on Monday. Rain will develop over parts of the Upper Mississippi Valley/Upper Great Lakes on Sunday evening that will expand into parts of Northern New England on Monday. Meanwhile, under the associated upper-level trough, showers and thunderstorms will develop over parts of the Great Basin to the Rockies through Monday. The areal coverage of the precipitation will be strongly influenced by daytime heating. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php