Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Sun Jul 14 2024 Valid 12Z Sun Jul 14 2024 - 12Z Tue Jul 16 2024 ....There is a Slight Risk of severe thunderstorms over parts of the Northern Plains into the Upper Mississippi Valley on Sunday and the Upper/Middle Mississippi Valley into the Great Lakes on Monday... ...There is a Slight Risk of excessive rainfall over parts of Middle Mississippi Valley into the Great Lakes on Monday... ...Dangerous and record-breaking heat begins to build across the Central Plains, Mid-Atlantic, and Southeast... A front extending from the Upper Mississippi Valley/Upper Great Lakes to the Northern Plains will move to the Great Lakes/Middle Mississippi Valley and trail off into the Northern High Plains by Monday. A wave of low pressure over the Northern Plains will move northeastward into Ontario, Canada, by Tuesday, bringing the cold front into the Great Lakes to the Middle Mississippi Valley/Central Plains. The boundary will produce showers and severe thunderstorms over the Northern Plains/Upper Mississippi Valley on Sunday. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northern Plains/Upper Mississippi Valley through Monday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Further, there is an increased threat of severe thunderstorm wind gusts of 65 knots and hail two inches or greater, mainly over parts of the Northern Plains. Also, showers and thunderstorms will develop over parts of the Great Lakes into parts of the Mid-Atlantic. Furthermore, upper-level energy and tropical moisture will produce showers and thunderstorms from parts of the Western Gulf Coast eastward to the Southeast. Additionally, moisture over the Southwest and diurnal heating will produce late afternoon into late evening showers and thunderstorms over parts of the Great Basin, Southwest, and Central/Southern Rockies. On Monday, a wave of low pressure along the front over the Upper Midwest will pull the front back over parts of the Great Lakes, creating showers and severe thunderstorms in some parts of the area. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Upper/Middle Mississippi Valley into the Great Lakes from Monday through Tuesday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Moreover, the showers and thunderstorms will produce heavy rain over parts of the Middle Mississippi Valley into the Great Lakes. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Middle Mississippi Valley into the Great Lakes from Monday into Tuesday 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. Also, upper-level impulses will create showers and thunderstorms over parts of the Lower Great Lakes into parts of the Mid-Atlantic. Furthermore, upper-level energy and tropical moisture will produce showers and thunderstorms from parts of the Southeast. Meanwhile, an upper-level subtropical high over the Great Basin/Southwest into the Central/Southern Rockies will weaken, allowing heat to expand over portions of the central and eastern U.S. on Sunday into Tuesday. Confidence is increasing in extremely dangerous, potentially deadly heat, particularly for urban areas in the Southeast and East Coast beginning Monday. Many daily record highs are possible for the East Coast, and numerous warm overnight lows will provide little relief from the heat overnight. Heat stress will build rapidly for those without adequate cooling or hydration. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php