Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 356 PM EDT Thu Aug 23 2018 Valid 00Z Fri Aug 24 2018 - 00Z Sun Aug 26 2018 ...There is a slight risk of severe thunderstorms over parts of the Northern and Central Plains... ...Heavy rain possible over parts of the Middle Mississippi Valley... An upper-level low over the Northern Plains will move eastward to the Upper Great Lakes by Saturday. The upper-level energy and upper-level jet dynamics will aid in producing showers and thunderstorms over parts of the Northern Plains into the Middle Mississippi Valley that will move eastward to the Great Lakes/Western Ohio Valley into the Middle Mississippi Valley and parts of the Southern High Plains by Saturday. In addition, tropical moisture and upper-level impulses will aid in triggering showers and thunderstorms over parts of the Southeast and the Eastern Gulf Coast through Saturday. Meanwhile, a front over the Pacific Northwest will move inland to the Northern Plains southwestward to the Great Basin by Saturday. Showers and thunderstorms will develop along and near the boundary over the Northern High Plains starting Friday evening. The showers and thunderstorms will move into the Northern Plains by Saturday. Additionally, monsoonal moisture and upper-level energy will aid in producing showers and thunderstorms over parts of the Southwest/Great Basin and the Central/Southern Rockies through Saturday. The showers and thunderstorms will have the greatest areal coverage during the late afternoon into the late evening on Thursday and Friday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php