Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 313 PM EDT Thu Jun 19 2025 Valid 00Z Fri Jun 20 2025 - 00Z Sun Jun 22 2025 ...There is a Slight Risk of excessive rainfall over parts of the Mid-Atlantic and Central Appalachians... ...There is an Enhanced Risk of severe thunderstorms over parts of the Mid-Atlantic on Thursday and Northern Plains on Friday... ...There is a Critical Risk of fire weather over parts of the Great Basin/Southwest... A front extending from the Lower Great Lakes to the Tennessee Valley will move off the Northeast Coast by Friday. The eastward-moving boundary will trigger showers and thunderstorms with heavy rain over the Mid-Atlantic. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Mid-Atlantic through Friday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas the most vulnerable. Furthermore, the front will trigger showers and thunderstorms with heavy rain over the Central Appalachians. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Central Appalachians through Friday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas the most vulnerable. In addition, the boundary will trigger showers and severe thunderstorms over parts of the Mid-Atlantic to the Northeast. Therefore, the SPC has issued an Enhanced Risk (level 3/5) of severe thunderstorms over the Mid-Atlantic through Friday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. A second front extending from the Upper Great Lakes westward to the Northern Intermountain Region fluctuates over the area, producing showers and severe thunderstorms over parts of the Northern Plains/Upper Mississippi Valley on Thursday evening. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northern Plains/Upper Mississippi Valley through Friday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. On Friday, the front will produce additional showers and severe thunderstorms over parts of the Northern Plains to the Upper Great Lakes. Therefore, the SPC has issued an Enhanced Risk (level 3/5) of severe thunderstorms over parts of the Northern Plains/Upper Mississippi Valley from Friday through Saturday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. However, there will be an added threat of severe thunderstorm wind gusts of 65 knots or greater and hail two inches or greater from the Northern Plains to the Upper Great Lakes. By Saturday, the threat of severe thunderstorms will be a Marginal Risk from the Northern High Plains to the Northeast. In addition, on Thursday, showers and thunderstorms will develop over parts of the Great Lakes to the Northeast and southward to the Gulf Coast. Showers and thunderstorms will continue over parts of the Southeast into the Central Gulf Coast Friday into Saturday. An upper-level low will move across the Pacific Northwest from Thursday into Saturday. The energy will produce rain and snow at the highest elevations over the Cascades overnight Thursday into Saturday. Further, rain will develop over parts of the Northern Intermountain Region and Northern Rockies on Friday morning and wet snow over parts of the Northern Rockies on Friday night, prompting a Winter Storm Watch over parts of Glacier National Park by Saturday. Elsewhere, deep boundary-layer mixing is expected across the Great Basin during the afternoon, with surface temperatures climbing into the 90s to 100 F and relative humidity falling into the single digits. The deep boundary-layer mixing into the strong flow aloft, coupled with a tightening regional pressure gradient, will contribute to an expansive area of 20-25 mph sustained southwesterly surface winds (with higher gusts) have prompted a Critical Risk of fire weather over parts of the Great Basin/Southwest Thursday into Saturday. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php