Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 355 PM EDT Fri Apr 19 2024 Valid 00Z Sat Apr 20 2024 - 00Z Mon Apr 22 2024 ...There is a Slight Risk of excessive rainfall over parts of the Southern Plains/Lower Mississippi Valley on Saturday... ...Light to moderate snow over parts of the Central Rockies and Central High Plains overnight Friday into Saturday and a second area of light snow over the Cascades and Northern Intermountain Region on Sunday... ...Strong to severe thunderstorms from the southern Mid-Atlantic, Southeast to the Southern Plains on Friday and Saturday... A front extending from Upstate New York southward to the Mid-Atlantic and then westward to the Western Gulf Coast will move off the Northeast and Mid-Atlantic Coast by Saturday afternoon. The boundary lingers along the Gulf of Mexico Coast through Sunday evening. As the front moves into the southern Mid-Atlantic/Southeast, showers with strong to severe thunderstorms will develop over the area. Therefore, the SPC has issued a Marginal Risk (level 1/5) of severe thunderstorms over parts of the Mid-Atlantic/Southeast through Saturday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. The area of showers and thunderstorms will extend into parts of the Lower Mississippi Valley and the Southern Plains through Friday night. Moreover, rain will develop over parts of the Northeast Friday night into Saturday as light snow showers develop over parts of the Upper Great Lakes, ending by Saturday afternoon. Overnight Friday into Saturday, upper-level energy and upslope flow associated with strong high pressure over the Northern High Plains will help produce light to moderate snow over parts of the Central Rockies and Central High Plains. On Saturday, as the front settles over the Gulf Coast, showers with strong to severe thunderstorms will develop over parts of the Southern Plains and Southeast. Therefore, the SPC has issued a Marginal Risk (level 1/5) of severe thunderstorms over two areas, the Southern Plains/Western Gulf Coast and the second area over the Southeast from Saturday into Sunday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. The showers and thunderstorms will also produce heavy rain over parts of the Southern Plains/Lower Mississippi Valley. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall with these thunderstorms. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable. On Sunday, the strong to severe thunderstorm threat has come to an end. However, showers and thunderstorms will continue over parts of the Southeast to the Southern Plains. Meanwhile, a front will come onshore over the Pacific Northwest Saturday afternoon and move eastward to the Northern High Plains and Great Basin by Sunday evening. The system will produce rain over parts of the Pacific Northwest Coast through Sunday evening. Furthermore, overnight Saturday, light snow will develop over the Cascades and parts of the Northern Intermountain Region by early Sunday morning, continuing into Sunday evening. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php