Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 341 PM EDT Wed Jul 15 2015 Valid 00Z Thu Jul 16 2015 - 00Z Sat Jul 18 2015 ...Severe thunderstorms and flash flooding possible for portions of the central plains and Midwest... ...Above average temperatures expected from the southern and central plains to the Southeast... An area of low pressure at the surface and an associated surface warm front will move across the central plains and Midwest tonight into Thursday morning. These surface features along with an upper-level disturbance will result in the development of scattered to widespread showers and thunderstorms this evening across the central plains which will move eastward across the Midwest on Thursday. The Storm Prediction Center has outlined a slight risk for severe thunderstorms through tonight in association with this system. Heavy rainfall may also result in the possibility of flash flooding in some areas. The surface low will continue to move northeastward to near Lake Michigan by Thursday morning, with showers and thunderstorms spreading across much of the Great Lakes on Thursday. A cold front will move across the northwestern U.S. tonight ahead of an upper-level trough moving into British Columbia. Moisture will be limited at first, with precipitation associated with the front remaining primarily confined to Canada through Thursday afternoon. After that time, as the system encounters slightly better moisture, scattered showers and thunderstorms are possible along and ahead of the front Thursday night into Friday from the northern Intermountain West into the northern plains. In the wake of this cold front, temperatures will be 5 to 10 degrees below average across the northwestern U.S. Across the southeastern U.S., a frontal boundary will become stationary tonight and will linger into Saturday. This boundary will generally serve as the northern extent of scattered afternoon and evening showers and thunderstorms. Relatively drier air north of the boundary will limit shower and thunderstorm activity. The Storm Prediction Center is forecasting a slight risk of severe thunderstorms this evening across portions of southern Georgia and coastal South Carolina. High pressure at the mid and upper-levels will keep afternoon high temperatures 5 to 10 degrees above average across the Southeast and extending into the southern/central plains through Friday. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php