Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 357 PM EDT Fri Jul 07 2017 Valid 00Z Sat Jul 08 2017 - 00Z Mon Jul 10 2017 ...Severe thunderstorms and flash flooding possible for the Ohio Valley Friday night... ...Above average temperatures expected for much of the western U.S. with afternoon thunderstorms.. A cold front stretching from the Great Lakes Region through the Ohio Valley, Mid-Mississippi Valley, and into the Central Plains will continue moving south and eastward over the next couple of days, causing showers and thunderstorms along and ahead of it. Through Friday night, the Ohio Valley in particular could see strong to severe thunderstorms due to this front. The Storm Prediction Center has outlooked an enhanced risk of severe weather for this area. Additionally, there is potential for flash flooding as heavy rainfall is possible in the Ohio Valley Friday night. Farther east, as moisture streams northward ahead of the front, portions of the Northeast may continue to see rain and thunderstorms that could contain locally heavy rain. This front will push eastward through the Northeast and Mid-Atlantic and southward through the Tennessee Valley, Lower Mississippi Valley, and Southern Plains on Saturday, bringing scattered thunderstorms to those areas. By Sunday, the front will linger across the Southeast, and scattered thunderstorms will continue there. A second frontal system will approach the Upper Midwest to Great Lakes region on Sunday as well, so another round of showers and thunderstorms will be possible for those areas. In the western U.S., an upper-level ridge is present, which will continue to cause extremely hot conditions in some areas through the weekend. Excessive Heat Warnings are in effect for much of the Desert Southwest through Saturday, with temperatures around 10 degrees above average. Farther north into the Great Basin and Northern Rockies, temperatures in the 90s and 100s are expected on Saturday, which is 10 to 20 degrees above average. Numerous daily temperature records may be tied or broken. The heat will expand eastward into the Northern Plains by Sunday. Isolated thunderstorms are expected in the interior western U.S. as well, mainly during the afternoon. Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php