Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 345 AM EDT Wed Jul 13 2016 Valid 12Z Wed Jul 13 2016 - 12Z Fri Jul 15 2016 ...Severe thunderstorms and heavy rainfall possible across portions of the plains and Mississippi valley... ...Below average temperatures expected from the northern Rockies to the northern plains... Another shot of cooler air will move through the northern High Plains today; which will overtake a quasi-stationary boundary across the central Plains tonight and into Thursday. Scattered to numerous showers and thunderstorms will develop along and ahead of the advancing front from the southern/central plains to the mid-Mississippi valley and Great Lakes. Some thunderstorms could produce severe weather and heavy rainfall. Please refer to products issued by the Storm Prediction Center for further details on the severe weather threat. The cold front is forecast to move through the Great Lakes region on Thursday and will shift the area of convection into the Appalachians and Northeast regions. Heavy rainfall may be possible today for portions of Kansas, Oklahoma, Missouri and Arkansas. These areas will have an increased risk for flash flooding. Much of the Southeast U.S will continue to have showers and thunderstorms through Thursday within the moist, unstable airmass. In the wake of the cold frontal passage, cooler air will infiltrate the northern Plains and Upper Midwest. Forecast maximums temperature for today are anticipated to range 5 to 15 degrees below average from the northern Rockies to the northern plains. On Thursday these cooler temperatures will spread into the Upper Midwest. Isolated to scattered showers and thunderstorms will remain possible across these areas as a series of fast-moving upper-level disturbances traverse the region. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php