Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 341 AM EDT Mon Sep 30 2024 Valid 12Z Mon Sep 30 2024 - 12Z Wed Oct 02 2024 ..There is a Slight Risk of excessive rainfall over parts of the Central Appalachians/Mid-Atlantic on Monday... ...There is a Critical Risk of fire weather over parts of the Northern/Central Plains on Monday... ...There are Excessive Heat Warnings and Heat Advisories over parts of Southern California and the Southwest... An upper-level low over the Ohio Valley/Central Appalachians will slowly weaken and move eastward to the Mid-Atlantic by Tuesday, with the energy moving off the Mid-Atlantic Coast by Tuesday evening. A rich pool of moisture extends from the Tennessee Valley to the Ohio Valley, and then the Mid-Atlantic will be impacted by upper-level dynamics to produce heavy rain over parts of the Central Appalachians/Mid-Atlantic. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Central Appalachians/Mid-Atlantic through Tuesday 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 Tuesday, the threat of excessive rainfall ends. Rain and showers will continue over parts of the Mid-Atlantic through Tuesday night. Meanwhile, a dry front extending from the Northern Plains to the Central High Plains/Central Rockies will move to the Lower Upper Great Lakes southwestward to the Southern Plains by Wednesday. On Tuesday, the front will intersect moisture over the Upper Midwest, producing light rain over parts of the Upper Great Lakes. By Tuesday afternoon, rain will expand along the boundary from the Ohio Valley to the Tennessee Valley. Light rain will move into the Lower Great Lakes/Central Appalachians by Wednesday. In addition, showers and thunderstorms will develop over parts of Florida from Monday into Wednesday. Ahead of the front, an upper-level ridge will extend from the Southwest to the Northern/Central Plains. The warm air associated with the upper-level ridge, strong gust wind, and dry fuels have prompted a Critical Risk of fire weather over the North/Central Plains on Monday. Moreover, the upper-level ridge over the Four Corners Region will create high temperatures over Southern California and the Southwest ranging from the upper 90s to 110s. Low temperatures will be in the upper 80s to low 90s, providing little relief from the heat overnight. The temperatures have prompted Excessive Heat Warnings and Heat Advisories over parts of Southern California and the Southwest. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php