Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 357 AM EDT Sat Jul 13 2024 Valid 12Z Sat Jul 13 2024 - 12Z Mon Jul 15 2024 ...There is a Slight Risk of severe thunderstorms over parts of the Northern Plains into Upper Mississippi Valley on Saturday and Sunday... ...There is a Slight Risk of excessive rainfall over parts of northern Mid-Atlantic on Saturday... ...Dangerous and record-breaking heat will continue for much of the West through Saturday, while sizzling temperatures will also begin to build across the Central Plains and Southeast... A weak front with tropical moisture will be quasi-stationary over parts of the Northeast, Mid-Atlantic, and Southeast through Sunday morning. Showers and thunderstorms will develop along and near the boundary as the tropical moisture produces heavy rain over parts of the Easter Seaboard. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall with these thunderstorms over parts of the northern Mid-Atlantic through Sunday 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, on Saturday, a front over the Northern Plains will move across the Northern Plains into the Upper Mississippi Valley and extending into the Upper Great Lakes by Monday. The boundary will produce showers and severe thunderstorms over the region. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northern Plains into Upper Mississippi Valley through Sunday 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 over parts of the Northern High Plains. Moreover, upper-level energy and tropical moisture over the Western and Central Gulf Coast will produce showers and thunderstorms. Furthermore, moisture streaming northward from the Gulf of California and weak upper-level energy will aid in producing scattered showers and thunderstorms over parts of Southern California and Southwest. On Sunday, a wave of low pressure along the front over the Upper Midwest will move from Montana to North Dakota, creating showers and severe thunderstorms in parts of the area. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northern Plains into Upper Mississippi Valley from Sunday through Monday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. 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. 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. Meanwhile, an upper-level subtropical high over the Great Basin/Southwest into the Central/Southern Rockies will allow an extremely dangerous heat wave to persist over the area. The upper-level ridging will produce a near all-time high temperature record, and heat will continue over portions of the Southwest through Sunday. This long-duration heat wave remains extremely dangerous and deadly if not taken seriously. Dozens of daily record high temperatures are forecast over much of the West through Sunday. Hazardous heat will expand in coverage over portions of the Middle Mississippi Valley and Southeast on Sunday and Monday. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php