Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 343 AM EDT Thu Sep 14 2017 Valid 12Z Thu Sep 14 2017 - 12Z Sat Sep 16 2017 ...There is a slight risk of severe thunderstorms over parts of the Southwest... ...Heavy rain possible over parts of the Upper Mississippi Valley/Upper Great Lakes and parts of the Northern High Plains/Northern Plains... ...Heavy wet snow for parts of the highest elevations of the Northern Rockies... Upper-level energy over the Ohio Valley that was once associated with Irma will slowly weaken and move eastward off New England Coast by Friday evening. The energy will aid in producing rain over parts of the Ohio Valley/Lower Great Lakes and the Central/Southern Appalachians that will end overnight Thursday. In addition, showers and thunderstorms will develop over parts of the Northern/Southern Mid-Atlantic into parts of New England that will move off the Northeast Coast by Friday morning. Rain showers will also develop over parts of the Ohio Valley/Mid-Atlantic into the Northeast on Friday afternoon into Friday evening. Meanwhile, upper-level energy over Southern California will move northeastward into the Northern Plains by Friday evening. The energy will aid in developing showers and thunderstorms over parts of Southern California and the Southwest/Great Basin along with parts of the Southern/Central Rockies that will end over Southern California overnight Thursday. The showers and thunderstorms will also end over parts of the Southwest and the Southern/Central Rockies on Friday. Moisture and weak upper-level impulses will aid in producing showers and thunderstorms over parts of the Southern High Plains starting overnight Thursday and continuing into Friday evening. A quasi-stationary front extending from the Upper Mississippi Valley/Upper Great Lakes southwestward to the Central Plains/Central High Plains into the Northern Rockies/Great Basin will aid in producing showers and thunderstorms over parts of the region through Friday evening. Additionally, an upper-level trough will move into the Northern Rockies on Thursday and linger over the area into Friday evening. Rain will develop over the Northern Rockies through Friday. As the upper-level trough moves over the area, the snow levels will lower overnight Thursday into Friday evening. Heavy wet snow will develop over the highest elevations of the Northern Rockies that will expand into lower elevations overnight Thursday into Friday. Elsewhere, tropical moisture over parts of Florida and the Southeast will aid in developing showers and thunderstorms over the region through Friday evening. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php