Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 224 PM EDT Mon Jun 20 2016 Valid 00Z Tue Jun 21 2016 - 00Z Thu Jun 23 2016 ...Severe thunderstorms possible through tonight from the mid-Mississippi valley to the lower Great Lakes... ...Severe thunderstorms and flash flooding possible Tuesday from portions of the Midwest to the Mid-Atlantic... ...Above average temperatures expected to continue for the western U.S... A cold front will move from the lower Great Lakes into the Mid-Atlantic and Northeast tonight, bringing areas of showers and thunderstorms to those regions. The trailing end of the frontal boundary will linger from the central plains into the mid-Mississippi valley, with showers and thunderstorms for those areas as well. The Storm Prediction Center is forecasting a slight risk of severe thunderstorms through tonight from portions of the mid-Mississippi valley to the lower Great Lakes/Northeast. Please refer to products issued by SPC for further details on the severe weather threat. On Tuesday, the cold front will move toward the Mid-Atlantic and Northeast coastline, bringing showers and thunderstorms to those areas. Areas of severe thunderstorms will be once again possible along the front on Tuesday across portions of the Mid-Atlantic as well as the central Appalachians and portions of the Tennessee/Ohio valleys. Isolated areas of flash flooding will also be a possibility. The portion of the front across the central plains/Mississippi valley will begin to slowly move north as a warm front on Tuesday ahead of a developing low pressure system crossing the Rockies. This will keep areas of thunderstorms a possibility along and north of the warm front, and severe thunderstorms as well as flash flooding are possible. By late Tuesday, the aforementioned low pressure system will begin to move from the Rockies into the northern High Plains, with showers and thunderstorms, some possibly severe, becoming more widespread by evening across the northern plains. This low pressure system will move east, with showers and thunderstorms spreading across the northern plains into the Midwest on Wednesday, with showers and thunderstorms spreading into the Great Lakes and Ohio valley. High pressure at the mid and upper-levels of the atmosphere will remain anchored from the southern plains to the Southwest through the next couple days, keeping hot temperatures in the forecast. Temperatures across the southwestern U.S. will slowly decrease through mid-week as high pressure overhead weakens slightly, although temperatures will remain above average. High temperatures on Tuesday and Wednesday are forecast to be 10 to 20 degrees above average across much of the Southwest as well as portions of the Rockies and the central/southern plains. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php