Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 354 AM EDT Tue Aug 31 2021 Valid 12Z Tue Aug 31 2021 - 12Z Thu Sep 02 2021 ...Tropical Depression IDA is forecast to slowly weaken while moving northeastward with a Moderate Risk of excessive rainfall from Southern Appalachians/Tennessee Valley and Ohio Valley/Central Appalachians through Wednesday morning... ...There is a Moderate Risk of excessive rainfall associated with IDA over the Central Appalachians/Mid-Atlantic/Northeast Wednesday into Thursday morning... ...There is a Slight Risk of severe thunderstorms over parts of the Southeast into the Southern Appalachians and over parts of the Mid-Atlantic through Wednesday morning... ...There is a Sight Risk of excessive rainfall over the Southwest into the Central/Southern Rockies as former T. C. NORAâ€S moisture moves over the region through Thursday morning... Tropical Depression IDA is forecast to slowly weaken and become a Post-Tropical Cyclone as the system continues to move northeastward into parts of the Mid-Atlantic by Thursday morning. However, IDA will continue to produce heavy rain along the path into Thursday. Therefore, the WPC has issued a Moderate Risk of excessive rainfall from Southern Appalachians/Tennessee Valley and Ohio Valley/Central Appalachians through Wednesday morning. The associated heavy rain will create numerous areas of flash flooding. Furthermore, many streams may flood, potentially affecting larger rivers along the track. Furthermore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Southeast into the Southern Appalachians through Wednesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. As IDA moves into the Mid-Atlantic on Wednesday, Heavy rain will develop over parts of the Mid-Atlantic into the Northeast. Therefore, the WPC has issued a Moderate Risk of excessive rainfall from Central Appalachians/Mid-Atlantic/Northeast from Wednesday into Thursday morning. The associated heavy rain will create numerous areas of flash flooding. Moreover, many streams may flood, potentially affecting larger rivers along the systemâ€s path. Additionally, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Mid-Atlantic on Wednesday into Thursday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Meanwhile, a quasi-stationary front extending from the Mid-Atlantic westward to the Middle Mississippi Valley, then northwestward into the Northern High Plains, will have pooling moisture and upper-level impulses flow along the boundary on Tuesday. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Mid-Atlantic through Wednesday morning unrelated to IDA. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. In addition, showers and thunderstorms will develop along the Gulf Coast with the very moist air in place from Tuesday into Thursday morning. Elsewhere, moisture associated with what was once Tropical Cyclone NORA will move over the Southwest into parts of the Great Basin and Central Rockies on Tuesday into Thursday, producing thunderstorms. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable through Thursday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable Tuesday into Thursday morning. Additionally, the fire weather threat increases over Northern California into parts of Idaho and Wyoming as Red Flag Warnings have been issued in these areas. Air Quality Alerts have also been published over much of the Pacific Northwest and California as well as parts of Wyoming and Colorado due to wildfire smoke. Ziegenfelder