Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 349 PM EDT Tue Sep 07 2021 Valid 00Z Wed Sep 08 2021 - 00Z Fri Sep 10 2021 ...There is a Slight Risk of severe thunderstorms over parts of the Great Lakes through Wednesday morning... ...There is a Slight Risk of excessive rainfall over parts of the Northeast from Wednesday into Thursday morning... ...A heatwave will encompass much of the West with record high temperatures possible... A front extending from the Great Lakes to the Southern High Plains will slowly move eastward off the Northeast and Mid-Atlantic Coast by Thursday evening. Showers and thunderstorms will develop along and ahead of the front over the Great Lakes/Ohio Valley that will move into the Northeast and Mid-Atlantic on Wednesday. Upper-level dynamics have led the SPC to issue a Slight Risk of severe thunderstorms over parts of the Great Lakes through Wednesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. The severe thunderstorm threat continues on Wednesday into Thursday morning over parts of the Northeast. In addition, the showers and thunderstorms will develop over parts of the Northeast that recently had heavy rain from IDA. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms on Wednesday into Thursday. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable from Wednesday through Thursday morning. Showers and thunderstorms will also develop over parts of the Southeast on Wednesday into Thursday. Elsewhere, an upper-level high over the Great Basin will aid in producing record high temperatures over the Western States through Thursday. Furthermore, the dry weather associated with the upper-level high will and gusty winds has led to an increase in the fire weather threat over parts of the Upper Midwest and California, with Red Flag Warnings over parts of the Northwest into the Northern Rockies. In addition, excessive Heat Warnings are posted over Southeastern California, while Heat Advisories are also posted over most of the state. However, Air Quality Alerts have also been published over parts of the Pacific Northwest, Idaho, Wyoming, and Colorado due to wildfire smoke. Ziegenfelder Graphics are available at www.wpc.ncep.noaa.gov/basicwx/basicwx ndfd.php