Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 332 AM EDT Tue Oct 29 2024 Valid 12Z Tue Oct 29 2024 - 12Z Thu Oct 31 2024 ...Moderate to heavy snow over parts of the Northern/Central Rockies on Tuesday... ...Temperatures will be 20 to 35 degrees above average over parts of the Central Plains to the Great Lake/Ohio Valley... ...There is a Slight Risk of severe thunderstorms over parts of the Middle/Lower Mississippi Valley and Central/Southern Plains on Wednesday... A wave of low pressure along a front over the Great Basin/Central Rockies will move northeastward to the Upper Mississippi Valley by Thursday. Ahead of the front, temperatures will be 20 to 35 degrees above average over parts of the Central Plains to the Great Lake/Ohio Valley. A warm front extending from the Upper Mississippi Valley to the Ohio Valley moves northeastward into Eastern Canada by Wednesday. Ahead of the warm front, showers and thunderstorms will develop over parts of the Great Lakes, ending by Tuesday afternoon. On Tuesday evening, rain will develop over parts of the Lower Great Lakes/Northeast and continue into Wednesday afternoon. On Tuesday, a wave of low pressure will produce moderate to heavy snow over parts of the Northern/Central Rockies and higher elevations of the eastern Great Basin. Rain will also develop over parts of the lower elevations of the Southwest, Great Basin, and Central Rockies. Moreover, weak onshore flow off the Pacific will produce rain over parts of the Pacific Northwest through late Tuesday evening. Light snow will continue on Wednesday over parts of the Northern/Central Rockies through late Wednesday night. Meanwhile, southeasterly flow off the Gulf of Mexico will create scattered showers and thunderstorms over parts of the Western Gulf Coast on Tuesday into Wednesday. Similarly, easterly flow off the Atlantic will produce showers and thunderstorms over parts of Florida through Thursday morning. Further, moist air flowing northward over the Plains will extend into the Upper Great Lakes on Wednesday, creating showers and thunderstorms over parts of the Northern Plains and Upper Mississippi Valley. Showers and strong to severe thunderstorms will develop ahead of the front over parts of the Middle Mississippi Valley to the Central/Southern Plains. Therefore, the SPC has issued a Marginal Risk (level 1/5) of severe thunderstorms over parts of the Middle Mississippi Valley to Central/Southern Plains through Wednesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. On Wednesday, showers and severe thunderstorms will develop along and ahead of the front over parts of the Middle/Lower Mississippi Valley and Central/Southern Plains. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over these areas from Wednesday through Thursday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Furthermore, moderate to heavy rain will develop along the front parts of the Mississippi Valley and the Central/Southern Plains. Therefore, the WPC has issued a Marginal Risk (level 1/4) of excessive rainfall over parts of the Mississippi Valley and parts of the Central/Southern Plains from Wednesday through Thursday morning. The associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain. Elsewhere, another front will come onshore over the Pacific Northwest and California on Wednesday into early Thursday morning. The system will produce rain and higher-elevation snow over parts of the Northwest into Northern/Central California. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php