Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 427 PM EDT Wed Sep 28 2016 Valid 00Z Thu Sep 29 2016 - 00Z Sat Oct 01 2016 ...There is a slight risk of severe thunderstorms over parts of the Mid-Atlantic... ...Heavy rain possible over parts of the Northern Mid-Atlantic into the Great Lakes... A deep upper-level low over the Ohio Valley will sink southward into the Southern Ohio Valley/Tennessee Valley by Friday. Circulation around the upper-level low will stream moisture off the Atlantic into the Mid-Atlantic/Great Lakes and the Ohio Valley. Showers and thunderstorms will develop along and near the associated front from parts of the Great Lakes/Ohio Valley to the Mid-Atlantic and the Southeast through Friday. Rain associated with the showers and thunderstorm will be heavy at times over parts of the Northern Mid-Atlantic/Central Appalachians and the Lower Great Lakes waning by Friday morning. Meanwhile, monsoonal moisture and daytime heating will aid in producing shower and thunderstorms over the Southwest/Great Basin and the Central/Southern Rockies through Friday. In addition, upper-level troughing and upper-level energy moving across the Northwest into the Northern High Plains will aid in producing showers and thunderstorms over parts of the Northern Rockies/Northern Intermountain Region Thursday morning into Friday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php