Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 326 AM EDT Mon Aug 1 2016 Valid 12Z Mon Aug 1 2016 - 12Z Wed Aug 3 2016 ...Severe thunderstorms possible across portions of the northern Plains and Upper Midwest... ...Heavy rain and flash flooding possible for the Northeast, Middle/Upper Mississippi valley and the Southwest... Multiple rounds of rain and thunderstorm activity are expected from the Upper Midwest to the East Coast through at least midweek. A slow moving frontal boundary will be in place, stretching from the central Plains to the Mid-Atlantic coast. A swath of heavier rainfall from the Gulf Coast to the coastal Carolinas is likely, where amounts may exceed an inch through Tuesday. Parts of New York and New England should also see some areas of moderate to heavy rainfall. An upper level trough over the northwest quadrant of the nation will result in cooler temperatures across the Pacific Northwest and northern Rockies, with a surface cold front slowly tracking across the Intermountain West. Showers and thunderstorms are forecast to develop along and ahead of the system as it continues to track eastward. Much of the Desert Southwest and surrounding southern Plains will continue to be quite warm under the upper-level ridge. Monsoonal flow streaming northward over the Four-Corners region will help fire off convection across New Mexico and Arizona. Locally heavy rainfall is anticipated over the higher terrain, which may cause some flooding issues. The heaviest rainfall is expected over southeastern Arizona. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php