Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 418 AM EDT Mon Sep 16 2013 Valid 12Z Mon Sep 16 2013 - 12Z Wed Sep 18 2013 ...Heavy rain possible over the extreme southern tip of Texas... ...Temperatures will be 10 to 20 degrees above average for part of the Northern High Plains... A front extending from the Northeast Coast to the Tennessee Valley then southwestward to the Southern High Plains will sink southward to the Southeast and the Gulf Coast States, with the western end of the boundary returning northward as a warm front by Monday evening into Tuesday. Rain will move off the Northeast/Mid-Atlantic by Monday evening. While showers and thunderstorms will develop over the Southeast near the boundary through Tuesday evening. Showers and thunderstorms will develop along the western end of the front from the Southern Rockies to the Middle Mississippi Valley. The showers and thunderstorms over the Central Plains/Middle Mississippi Valley are also associated with upper-level energy over the Central High Plains that moves northeastward to the Middle/Lower Missouri Valley by Tuesday. Likewise, the showers and thunderstorms will move northeastward to Middle/Lower Missouri Valley. The showers and thunderstorm over the Southern Rockies/Southern High Plains will slowly wane and end on Tuesday afternoon. Easterly flow off the Gulf of Mexico and moisture from Ingrid will produce showers and thunderstorms over the Lower Rio Grande Valley that will slowly wane to light showers and thunderstorms by Tuesday. In an analogous manner, easterly flow off the Atlantic will aid in producing showers and thunderstorms over the southern portions of Florida and along parts of the Eastern Gulf Coast through Tuesday. Another front over the Northern Rockies will move slowly eastward to the Northern High Plains/Northern Rockies by Tuesday. Energy associated with the upper-level trough that is also moving inland, behind the boundary, will produce showers and thunderstorms over parts of the interior Pacific Northwest will move eastward to the Northern High Plains/Northern Rockies by Tuesday. Rain will develop mainly near the Northwest Coast also through Tuesday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php