Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 508 PM EDT Wed Mar 22 2023 Valid 00Z Thu Mar 23 2023 - 00Z Sat Mar 25 2023 ....There is a Slight Risk of severe thunderstorms over parts of the Lower Mississippi/Tennessee Valleys and Southeast through Wednesday morning... â€There is a Marginal Risk of excessive rainfall over parts of the Western Ohio Valley and Middle /Lower Mississippi Valley through Wednesday morning... ...Snow for parts of the Cascades and the Northern Rockies... On Tuesday, a front extending from the Upper Great Lakes to the Lower Mississippi Valley will move slowly eastward off the East Coast by Thursday morning. Showers and thunderstorms will develop along and ahead of the boundary from the Ohio Valley to the Lower Mississippi Valley/Southeast and rain over parts of the Great Lakes. The system will produce showers and severe thunderstorms over the Lower Mississippi/Tennessee Valleys and Southeast. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Lower Mississippi/Tennessee Valleys and Southeast through Wednesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. In addition, rain will develop over parts of the Great Lakes/Ohio Valley. The rain and showers/thunderstorms have the potential to produce heavy rain over parts of the Middle Mississippi and Western Ohio Valleys. Therefore, the WPC has issued a Marginal Risk of excessive rainfall with these thunderstorms over parts of the Western Ohio Valley and Middle /Lower Mississippi Valley through Wednesday morning. The associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain. The threat of severe thunderstorms and excessive rainfall ends as the front moves eastward on Wednesday. However, rain will continue over parts of the Great Lakes/Ohio Valley, moving into the Northeast by Wednesday evening and will begin to taper off by Thursday. Moreover, showers and thunderstorms will continue over parts of the Southeast on Wednesday and move off the Southeast Coast by Thursday. Meanwhile, weak low pressure and associated front over parts of the Northeast will slowly dissipate on Tuesday morning. However, the rain will gradually taper off yet linger into Wednesday. Elsewhere, a front over the Northern Intermountain Region to Northern California will slowly dissipate overnight Tuesday. The system produces light rain and higher-elevation snow, with snow over the Northern Rockies. The rain and higher elevation snow will continue over the Northwest into the Northern Rockies on Wednesday as additional upper-level energy moves onshore over the Northwest. Overnight Wednesday into Thursday morning, snow will develop over parts of the Central Rockies. The snow will result in reduced visibility and hazardous driving conditions. Therefore, the winter weather has prompted Winter Weather Advisories over parts of the Northern Rockies and Cascades. Ziegenfelder Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php