Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 306 AM EDT Fri Jul 05 2013 Valid 12Z Fri Jul 05 2013 - 12Z Sun Jul 07 2013 ...Heavy rain threat continues across the Southeast, Tennessee and Ohio Valleys... ...the area of excessive heat continues to shrink out west... A very persistent flow of tropical air circulating northward around a strong cell of high pressure over the western Atlantic and a slow moving upper level trough will continue to bring a large area of showers and thunderstorms for the next several days from Florida and the Southeast northward across the Tennessee and Ohio Valleys. Satellite imagery shows this large plume of moisture from the Tropics converging across the Southeast northward toward the Great Lakes. Within this area of precipitation, some of the showers and thundershowers are expected to be quite heavy with the threat of flash flooding occurring each day. Diurnal fluctuations in heating will increase/decrease the areas during day/night. As of tonight, a large area of flash flood watches remains across much of the Southeast, eastern Tennessee Valley and Ohio Valley. The area of excessive heat has shrunk out west but is expected to continue very hot and dry conditions across interior California and portions of the Southwest for the next few days. There are also expected to be scattered thunderstorms from the Great Basin across parts of the Southwest that can both locally cool areas but also continue the threat of fires as well. Across northern California, the heat is expected to break tomorrow as cooler air finally moves inland across the northern half of the state. In addition, cooler temperatures are expected across much of the Pacific NW and will reach across Montana over the next couple days. Kocin Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php