Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 343 AM EDT Wed Jun 15 2016 Valid 12Z Wed Jun 15 2016 - 12Z Fri Jun 17 2016 ...Flash flooding and severe weather to impact the central and eastern portions of the U.S. over the next few days... Scattered showers and thunderstorms will persist through the end of the week spanning from the Upper/Middle Mississippi valley to the central Appalachians/Mid-Atlantic. An upper level low moving across the Great Lakes today will reach the Mid-Atlantic by Thursday. Warm, moist and unstable air ahead of the approaching low will allow for the development and continuation of convection. Some of these storms will have the potential to become severe across Wisconsin and the Ohio valley today - the Storm Predictions Center has highlighted these locations as having a slight risk. Additionally, heavy rainfall may lead to flash flooding - an excessive rainfall outlook has been issued for portions of the Pennsylvania, Maryland and Virginia. The area of increased threat for severe storms will shift over the central Appalachians and surrounding areas on Thursday. Coastal areas in the Mid-Atlantic will continue to have an elevated risk for heavy rain. Rainfall amounts across the northern Mid-Atlantic are forecast to be 1 to 2 inches through Saturday morning, with localized higher amounts possible. Daytime heating, combined with a moist and unstable airmass, will keep ongoing scattered convection across the Southeast. Rain amounts will of 1 to 2 inches are expected through the end of work week. Light to moderate rain is forecast for the Pacific Northwest and Intermountain West as an upper level low slowly moves south and east. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php