Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Fri Aug 31 2018 Valid 00Z Sat Sep 01 2018 - 00Z Mon Sep 03 2018 ...There is a slight risk of severe thunderstorms over parts of the Upper/Middle Mississippi Valley... ...Heavy rain possible for the Upper/Middle Mississippi Valley into parts of the Central Plains... ...Heavy rain possible over parts of the Central Gulf Coast... A front extending from the Northern Plains/Upper Mississippi Valley to the Central Plains westward to parts of the Great Basin will slowly move eastward to the Upper Great Lakes southwestward to the Central Plains then westward to parts of the Great Basin by Saturday afternoon. The boundary will slowly dissipate by Saturday evening. Showers and thunderstorms will develop along and near the front from the Upper Mississippi Valley into parts of the Central Rockies that will move eastward to the Great Lakes into parts of the Middle Mississippi Valley and parts of the Central/Southern Plains by Sunday. Showers and thunderstorms will continue along the old boundary on Saturday afternoon into Sunday. In addition, tropical moisture and daytime heating will aid in producing showers and thunderstorms over parts of the Lower Great Lakes into the Mid-Atlantic and over parts of the Ohio/Tennessee Valleys as well as the Gulf Coast through Sunday. Meanwhile, a second front over Western Canada will move southeastward to the Upper Mississippi Valley into the Northern Plain then northwestward across parts of the Northern High Plains/Northern Rockies by Sunday. Showers and thunderstorms will develop along and near the boundary overnight Saturday that will move eastward to the Upper Mississippi Valley into the Northern Plains by Sunday. Monsoonal moisture and daytime heating will aid in producing showers and thunderstorms over parts of the Southwest/Great Basin and the Central/Southern Rockies overnight Friday into Sunday. The greatest areal coverage will be during the late afternoon into the late evening. Additionally, upper-level energy over the Southern Rockies will mover eastward into the Central/Southern High Plains overnight Saturday into Sunday. The energy will aid in developing showers and thunderstorms over region overnight Saturday into Sunday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php