Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 743 PM EDT Fri May 28 2021 Valid 00Z Sat May 29 2021 - 00Z Mon May 31 2021 ...There is an Enhanced Risk of severe thunderstorms and a Slight Risk of excessive rainfall over parts of the Southern Plains, tonight... ...Below average temperatures across much of the central and eastern United States, while heat builds over the West this Memorial Day weekend... A front extending from the Mid-Atlantic to the Central Appalachians, then southwestward to the Southern High Plains, will move off the Atlantic Coast and the Gulf Coast by Saturday evening. Additionally, there is an upper-level low over the Western Ohio Valley/Upper Great Lakes that will slowly move to the Mid-Atlantic by Sunday evening. The low will produce rain over parts of the Ohio Valley into parts of the Northeast with embedded thunderstorms over the Southern Ohio Valley/Tennessee Valley and Mid-Atlantic Saturday morning. The rain will continue over the Northeast/Mid-Atlantic, with scattered rain showers over parts of the Western Ohio Valley on Saturday. The rain will continue over the Mid-Atlantic through Sunday evening. The upper-level low will also keep maximum daytime temperatures low over the central and eastern U.S., with several areas have of the Ohio Valley into the Northeast/Mid-Atlantic having record-making low maximum daily temperatures. Along the western end of the front, showers and thunderstorms will develop over parts of the Southern Plains through late Saturday night. The SPC has issued an Enhanced Risk of severe thunderstorms over parts of the Southern Plains through Saturday morning. The hazards associated with the severe thunderstorms are frequent lightning, severe thunderstorm wind gust, hail, and a few tornadoes. Additionally, there is a 10% or greater probability of two-inch hail or larger over parts of the Southern Plains into the Southern High Plains through Saturday morning. The thunderstorms will produce heavy rain. The WPC has issued a Slight Risk of excessive rainfall over parts of the Southern Plains through Saturday morning. The heavy rain will create scattered areas of flash flooding, with urban areas, roads, and small streams being the most vulnerable. The severe thunderstorm threat will linger over the Central/Southern High Plains through Monday. Likewise, the excessive rainfall threat will continue over parts of the Central/Southern High plains into Monday, too. Meanwhile, upper-level energy moving across the Northern Tier States will produce rain and thunderstorms over parts of the Pacific Northwest/Northern Rockies through Friday night. On Saturday, the area of rain and thunderstorms will move into the Northern Central Plains and extend from the upper Mississippi Valley to the Southern Plains on Sunday. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php