Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 327 PM EDT Sun Oct 20 2024 Valid 00Z Mon Oct 21 2024 - 00Z Wed Oct 23 2024 ...There is a Slight Risk of excessive rainfall over parts of the Southern High Plains on Sunday... ...There is a Slight Risk of severe thunderstorms over parts of the Southern High Plains on Sunday... ...Temperatures will be 20 to 30 degrees above average over the Northern Plains, Upper/Middle Mississippi Valley, and Upper Great Lakes... An upper-level low over the Four-Corners Region will move to the Great Lakes by Tuesday evening. The system will produce an isolated area of snow overnight Sunday to late Monday afternoon over the Central Rockies. In addition, the dynamic associated with the upper-low will produce showers and severe thunderstorms over parts of the Southern High Plains. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Southern High Plains through Monday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Furthermore, the storms will produce heavy rain over parts of the Southern High Plains. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Southern High Plains through Monday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas the most vulnerable. On Monday, showers and thunderstorms will develop over parts of the Central/Southern Plains through late Monday night. Moreover, ahead of the upper-level low, an upper-level ridge will allow temperatures to be 20 to 30 degrees above average over the Northern Plains, Upper/Middle Mississippi Valley, and Upper Great Lakes. Meanwhile, onshore flow off the Gulf of Mexico will create scattered showers and thunderstorms over the southern portion of Texas through Monday evening. Additionally, onshore flow off the Atlantic will produce scattered showers and embedded thunderstorms over parts of Florida through Tuesday evening. Elsewhere, a front over the Pacific Northwest on Sunday moves inland to the Upper Great Lakes, Central Rockies, and Northern Intermountain Region by Tuesday evening. The system will produce rain over parts of the Pacific Northwest through Tuesday. After the front passes the Cascades, snow will develop over parts of the highest elevations of the Cascades on Monday. Also, rain will expand on Monday into parts of the Northern Rockies/Northern High Plains. Overnight Monday, showers and thunderstorms will develop over parts of the Upper Midwest. The atmosphere will become more stable on Tuesday afternoon into evening, producing rain over parts of the Northern Plains/Upper Mississippi Valley. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php