Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 326 AM EDT Fri Jul 13 2018 Valid 12Z Fri Jul 13 2018 - 12Z Sun Jul 15 2018 ...Heavy rain possible across portions of the Central Plains into the Upper Mississippi Valley... ...Heavy rain possible over parts of Arizona... Tropical moisture extending from the Southeast to the Southern Plains along with daytime heating will aid in producing scattered showers and thunderstorms from parts of the Western Gulf Coast eastward to the Southeast through Saturday evening. In addition, the northern portion of a front extending from the Upper Great Lakes southwestward to the Central Plains will move eastward to the Lower Great Lakes/Eastern Ontario by Saturday night. The western portion of the front will be quasi-station through Saturday evening into Sunday. Showers and thunderstorms will develop along the boundary over the Upper Great Lakes into the Middle Missouri Valley that will move eastward to the Lower Great Lakes/Northeast by Saturday night. Along the western end of the front, showers and thunderstorms will develop along and near the boundary from the Middle Missouri Valley to the Central Plains through Sunday morning. Meanwhile, monsoonal moisture and daytime heating will aid in producing showers and thunderstorms over parts of the Southwest, Southern Rockies, and parts of the Great Basin through Saturday evening. The greatest areal coverage of the showers and thunderstorms will be during the late afternoon into late evening Friday into Saturday. Additionally, a front moving southward out of Western Canada will move into the Northern High Plains on Saturday morning moving into the Northern Plains by Saturday evening. Showers and thunderstorms will develop along the boundary over parts of Northern Plains into parts of the Northern High Plains on Saturday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php