Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 250 PM EDT Sun Jul 17 2016 Valid 00Z Mon Jul 18 2016 - 00Z Wed Jul 20 2016 ...Severe thunderstorms and heavy rain possible from portions of the Midwest to the Northeast... ...Monsoonal moisture will keep scattered showers and thunderstorms in the forecast for the Four Corners region... ...Temperatures will be above average across much of the central and eastern U.S. and below average on the West Coast... A cold front will sweep eastward across the Midwest and Great Lakes tonight and into the central Appalachians and Northeast on Monday. The system will produce scattered to numerous showers and thunderstorms, some of which could become severe in addition to producing heavy rainfall. Please refer to products issued by the Storm Prediction Center for further details on the severe weather threat. Farther south, scattered afternoon and evening showers and thunderstorms will persist across the Gulf Coast and Southeast as a warm, moist, and unstable air mass remains in place. By Tuesday, showers and thunderstorms should become a little more numerous across the Carolinas as the cold front approaches from the northwest. Monsoonal moisture transported into the southwestern U.S. on the western side of an a ridge of high pressure will keep scattered afternoon and evening showers and thunderstorms in place across the Four Corners region into Monday and Tuesday. Farther north, and upper-level low over the Pacific Ocean will move very slowly into the Pacific Northwest through the next couple days. This will keep scattered showers and thunderstorms in place from the Pacific Northwest into the northern Rockies along and north of a stationary frontal boundary. By Monday afternoon, a weak wave of low pressure will form along this frontal boundary and move into the northern plains, bringing scattered showers and thunderstorms with it. Temperatures are forecast to be 5 to 10 degrees above average across much of the central and eastern U.S. through the next couple days as high pressure aloft remains dominant. Across the West Coast, the influence of the upper-level low moving onshore will keep conditions cooler, with temperatures expected to be 5 to 15 degrees below average through Monday and Tuesday. Ryan Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php