Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 441 AM EDT Mon Oct 04 2021 Valid 12Z Mon Oct 04 2021 - 12Z Wed Oct 06 2021 ...There is a Slight Risk of excessive rainfall over parts of the Southeast through Tuesday morning... ...Air Quality Alerts over the San Joaquin Valley through Monday... ...Temperatures will be 10 to 25 degrees above average over parts of the Northern/Central High Plains... A quasi-stationary front extending from the Northeast to the Great Lakes then southwestward to the Lower Mississippi Valley will remain primarily stationary as a low develops over parts of the Lower Mississippi Valley by Wednesday. Moisture from the Gulf of Mexico will stream northward over the Central Gulf Coast to the Great Lakes and Northeast. Showers and thunderstorms will develop along and near the boundary. Some storms produce heavy rain from the Central Gulf Coast to the Southeast. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms over parts of the Southeast. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable through Tuesday morning. The threat of excessive rainfall will continue, however increasing in areal coverage over the Central Gulf Coast, Southeast, and Southern Appalachians on Tuesday into Wednesday morning. Rain will continue over the Northeast through Tuesday evening. The showers and thunderstorms will slowly expand into parts of the Mid-Atlantic/Southeast today. Meanwhile, moisture will stream into Southern California and the Southwest as upper-level energy begins to move over Southern California. The moisture and energy will produce showers and thunderstorms over parts of Southern California and the Southwest tonight into Tuesday. Additionally, a front will move into Pacific Northwest on Tuesday, producing light rain over parts of the Northwest into Northern California Furthermore, the smoke from wildfires will lead to poor air quality over the San Joaquin Valley of California, where Air Quality Alerts are in effect through today. Additionally, an upper-level ridge will develop over parts of the Rockies as temperatures will become 10 to 25 degrees above average over parts of the Northern/Central High Plains. Ziegenfelder Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php