Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 500 AM EDT Mon Aug 26 2013 Valid 12Z Mon Aug 26 2013 - 12Z Wed Aug 28 2013 ...Record heat will continue across the Upper Midwest... ...Severe storms will be possible over portions of the Upper Midwest and Great Lakes... ...Another day of widespread showers and thunderstorms expected across the Southwest... Record heat will continue across the Upper Midwest the next few days thanks to an expansive upper ridge anchored over the Central Plains and Middle Mississippi Valley. Excessive heat warnings and heat advisories remain in effect where well above normal temperatures will combine with high dew points to create heat indices in the triple digits. In addition to the heat...impulses of energy rounding the northern periphery of the upper ridge over the Central U.S. will help trigger showers and thunderstorms as they streak from the Upper Midwest to the Northeast. These storms will be developing in a very ripe environment...so there will be a threat for convection to become organized and potentially produce heavy downpours and severe weather. To the south of the expansive ridge...energy aloft moving westward in the northern Gulf will continue to produce showers and thunderstorms along the western Gulf Coast and eventually South Texas. Given the amount of moisture that will be available...these storms are expected to produce some moderate to locally heavy rains across southern portions of the Lone Star state. Conditions will remain favorable for another day of numerous showers and thunderstorms across the Southwestern U.S. on Monday. Moderate to locally heavy rains will be possible again on Tuesday...but the widespread threat for flash flooding should start to diminish as the remnants from post-tropical cyclone Ivo continue to weaken and moisture thins out a bit across the region. Farther north...moderate to heavy rains will be possible across the Pacific Northwest as an upper trough attempts to dig into the Western U.S.. Gerhardt Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php