Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 324 AM EDT Wed Sep 06 2023 Valid 12Z Wed Sep 06 2023 - 12Z Fri Sep 08 2023 ...There is a Slight Risk of severe thunderstorms over parts of the Lower Mississippi Valley/Tennessee Valley on Wednesday... ...There are Heat Advisories over parts of the Northeast and Southern Plains/Lower Mississippi Valley on Wednesday... ...Air Quality Alerts over parts of the Northern High Plains, Central Plains, and Upper Mississippi Valley on Wednesday... On Wednesday, a front extending from the Upper Mississippi Valley/Upper Great Lakes will move eastward to the Lower Great Lakes, Mid-Atlantic, Southeast, and Lower Mississippi Valley by Friday. On Wednesday, the system will create showers and thunderstorms from the Great Lakes southward to the Tennessee/Lower Mississippi Valleys. The front will also produce showers and severe thunderstorms over parts of western Tennessee, northern Mississippi, northeastern Louisiana, and extreme southeastern Arkansas. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Lower Mississippi Valley/Tennessee Valley through Thursday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. On Thursday, the threat of severe thunderstorms reduces slightly. As the front moves eastward, showers and strong to severe thunderstorms will develop over parts of New York State, Pennsylvania, Maryland, Virginia, West Virginia, and parts of New Jersey/Delaware. Therefore, the SPC has issued a Marginal Risk of severe thunderstorms over parts of the Northeast, Mid-Atlantic, and Central Appalachians from Thursday into Friday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, and a minimal threat of tornadoes and hail. Moreover, upper-level energy and a developing front over the Northern Rockies will produce showers and thunderstorms over parts of the Northern Intermountain Region/Northern Rockies from Wednesday into Wednesday night. Furthermore, an upper-level impulse will create showers and thunderstorms over parts of the Middle/Lower Mississippi Valley and Southern Plains late Thursday night into Friday. Meanwhile, upper-level ridging over the Northeast will wane on Wednesday as upper-level energy moves eastward from the Great Lakes. Unfortunately, the hot temperatures over the region will continue into Thursday, prompting Heat Advisories over the Northeast on Wednesday. In addition, an upper-level high will return to Texas, aiding in the development of hot temperatures over the region prompting Heat Advisories over the Southern Plains/Lower Mississippi Valley. The hot temperatures will continue over the area through Friday. Lastly, smoke from wildfires in West-Central Canada will reduce air quality over parts of the Northern High Plains, Central Plains, and Upper Mississippi Valley, prompting Air Quality Warnings and Dense Smoke Advisories over the area. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php