Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 307 AM EDT Wed Aug 06 2025 Valid 12Z Wed Aug 06 2025 - 12Z Fri Aug 08 2025 ...There is a Slight Risk of excessive rainfall over parts of the Southeast on Wednesday... ...There is a Slight Risk of severe thunderstorms over parts of the Northern High Plains on Thursday... ...Air Quality Alerts over parts of the Upper Midwest and parts of the Northeast... ...There are Extreme Heat Warnings and Heat Advisories over parts of Southeastern California and the Southwest... A front lingering from the Southeast will remain quasi-stationary along the Gulf Coast through Friday. The front and tropical moisture will trigger showers and thunderstorms, accompanied by heavy rain, over parts of the Southeast/southern Mid-Atlantic. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Southeast/southern Mid-Atlantic through Thursday morning. The associated heavy rain will primarily create localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas being the most vulnerable. Additionally, on Wednesday, another weak front will move over parts of the Northern/Central Plains into the Central Rockies, slowly lifting northward to the Northern Plains/Northern Rockies by Thursday. The system, combined with a steady source of moisture, will produce showers and strong to severe thunderstorms over parts of the Northern/Central Plains into the Middle Mississippi Valley. Therefore, the SPC has issued a Marginal Risk (level 1/5) of severe thunderstorms over parts of the Northern/Central Plains into the Middle Mississippi Valley through Thursday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. Furthermore, upper-level energy will produce showers and thunderstorms over parts of the Upper Mississippi Valley, the Great Lakes, the Ohio/Tennessee Valleys, as well as the Northeast and Central/Western Gulf Coast on Wednesday. Meanwhile, a third front will begin to move onshore over the Pacific Northwest on Wednesday, moving eastward to the Northern Intermountain Region and Northern California, and dissipating by Thursday. The energy will merge with the second front over the Northern Intermountain Region/Southwest, moving eastward to the Upper Mississippi Valley/Northern Plains and then the Central Rockies and Great Basin by Friday. The storm will produce showers and rain over parts of the Pacific Northwest on Wednesday. Behind the front, weak onshore flow will aid in creating showers and rain over parts of the Pacific Northwest and Northern Intermountain Region into Thursday. Moreover, on Thursday, tropical moisture over the Southeast, along with a lingering boundary, will produce showers and thunderstorms with moderate to heavy rain over parts of the Southeast/southern Mid-Atlantic. Therefore, the WPC has issued a Marginal Risk (level 1/4) of excessive rainfall over parts of the Southeast/southern Mid-Atlantic from Thursday through Friday morning. The associated heavy rain will create localized areas of flash flooding, particularly in areas that experience rapid runoff due to heavy rain. In addition, the front moving across the Northern Rockies/Northern Plains on Thursday will produce showers and severe thunderstorms over parts of the Northern High Plains. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northern High Plains from Thursday through Friday morning. The hazards associated with these thunderstorms include frequent lightning, severe thunderstorm wind gusts, hail, and occasional tornadoes. There is an added threat of hail two inches or greater over western North Dakota, northwest South Dakota, and extreme eastern Montana. Furthermore, moderate to heavy rain is expected to accompany the thunderstorms over the Northern Plains. Therefore, the WPC has issued a Marginal Risk (level 1/4) of excessive rainfall over parts of the Northern Plains from Thursday through Friday morning. The associated heavy rain will create localized areas of flash flooding, particularly in areas that experience rapid runoff due to heavy rain. Moreover, showers and thunderstorms will develop from the Upper Mississippi Valley/Great Lakes southward to the Gulf Coast and parts of the Northeast/Mid-Atlantic on Thursday. Showers and thunderstorms will also develop over parts of the Southwest, Southern Rockies, and Central/Southern Plains. Meanwhile, smoke from wildfires in Canada has prompted Air Quality Alerts over parts of the Upper Mississippi Valley, Upper Great Lakes, and the Northeast/northern Mid-Atlantic on Wednesday. Furthermore, an upper-level high over the Southwest will produce upward-trending temperatures across the Desert Southwest. High temperatures are expected to reach the mid-110s on Wednesday through Friday. The most significant heat is forecast to focus over central and southern Arizona with widespread Major to Extreme Heat Risk. A Widespread Major to locally Extreme Heat Risk will also extend into Southern California. There are Extreme Heat Warnings over parts of Southeastern California and the Southwest. Furthermore, Heat Advisories are in effect for parts of Southern California, southern New Mexico, and southwestern Texas. Stay informed and take steps to protect yourself from heat-related illnesses. For information on staying cool and safe, visit www.weather.gov/safety/heat. As temperatures rise, limit outdoor activity, stay hydrated, and ensure access to air-conditioning and other cooling areas. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php