Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 452 PM EDT Sat Aug 03 2024 Valid 00Z Sun Aug 04 2024 - 00Z Tue Aug 06 2024 ...There is a Moderate Risk of excessive rainfall over parts of the Eastern Gulf Coast and Southeast on Sunday and Monday... ...There is a Slight Risk of excessive rainfall over parts of the Northeast/northern Mid-Atlantic, southern Mid-Atlantic/Southeast, and southwest tip of Florida on Saturday evening... ...There is a Slight Risk of severe thunderstorms over parts of the Northern Plains and Upper Mississippi Valley and the Northeast Coast to Southern Mid-Atlantic on Saturday evening... ...There are Excessive Heat Warnings over parts of the Pacific Northwest, Great Basin, Southeastern California, and the Southwest, and Heat Advisories over parts of the Northern Plains, Northern Rockies, and the Gulf Coast... ...Tropical Depression Four, which is forecast to become Tropical Storm Debby, will bring hazardous rainfall, strong winds, and life-threatening storm surge inundation to portions of Florida on Sunday evening into Monday... A weak front extending from the Mid-Atlantic to the Southeast and then Westward into the Southern Plains will slowly move eastward over parts of the Northeast Coast and will be quasi-stationary over the southern and western parts of the area before dissipating by Monday. The boundary will aid in triggering showers and severe thunderstorms over parts of the Northeast Coast to the Southern Mid-Atlantic. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northeast Coast to Southern Mid-Atlantic through Sunday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a minimal threat of tornadoes. In addition, the showers and thunderstorms will create heavy rain over parts of the Northeast/northern Mid-Atlantic and a second area over parts of the southern Mid-Atlantic/Southeast. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over parts of the Northeast/northern Mid-Atlantic and a second area over parts of the southern Mid-Atlantic/Southeast 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. Moreover, heavy rain associated with Tropical Depression Four, which is forecast to become Tropical Storm Debby, will develop over parts of the southwestern parts of the Florida peninsula. Therefore, the WPC has issued a Slight Risk (level 2/4) of excessive rainfall over the southwestern parts of the Florida peninsula 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. A second front extending from the Upper Great Lakes to the Northern Plains and then to the Northern Rockies will go south and eastward to the Northeast to Ohio Valley and then to the Central Plains by Monday. The front will trigger showers and severe thunderstorms over parts of the Northern Plains/Upper Mississippi Valley. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over parts of the Northern Plains/Upper Mississippi Valley through Sunday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Additionally, there is a threat of hail two inches or greater over parts of central Minnesota and northeastern South Dakota. As the front moves eastward and southward, the system will create showers and thunderstorms from parts of the Northeast to the Midwest and into the Northern Rockies on Sunday and Monday. Furthermore, showers and thunderstorms will develop over parts of the Eastern Seaboard on Sunday and from the southern Mid-Atlantic to the Southeast on Monday. Meanwhile, upper-level ridging over the Northern Intermountain Region to the Southwest will produce above-average temperatures, spawning Excessive Heat Warnings over parts of the Pacific Northwest, Northern Intermountain Region, Great Basin, Southeastern California, and the Southwest. Another day of excessive heat is expected on Saturday for the interior section of the Northwest, with areas of major to locally extreme HeatRisk before the heat gets less intense next week. The focus of excessive heat will shift to southern California and the Desert Southwest this weekend, where it will then persist through the first half of next week. The prolonged nature of the heat will increase the risk of heat-related illness. The developing high-pressure center over the Intermountain West will maintain fire weather concerns across the region as winds increase and monsoonal moisture brings the threat of lightning and new potential wildfires. Moreover, a heatwave is expected to impact the Plains during the first half of next week as Triple-digit high temperatures are expected to spread southward down the Plains this weekend and into early next week ahead of a cold front. Heat indices could exceed 105 degrees at the hottest locations. Further, increasing heat and humidity will develop from the Mid-South to the Gulf Coast for next week. The combination of high temperatures increasing into the lower 100s along with high humidity will result in major to extreme HeatRisk. The heat and high humidity will expand across much of the Mid-South and down along the Gulf Coast through much of next week. Moreover, what is forecast to become Tropical Storm Debby is forecast to move northward over the Gulf of Mexico, moving to the Apalachee Bay area by early Monday morning and into southern Georgia by Monday evening. The storm will produce heavy rain over the Apalachee Bay area on Sunday. Therefore, the WPC has issued a Moderate Risk (level 3/4) of excessive rainfall from Sunday into Monday morning. The associated heavy rain will create numerous areas of flash flooding. Furthermore, many streams may flood, potentially affecting larger rivers. Likewise, on Monday, what is forecast to be Tropical Storm Debby will continue to produce heavy rain over parts of the Southeast. Therefore, the WPC has issued a Moderate Risk (level 3/4) of excessive rainfall on Monday. The associated heavy rain will create numerous areas of flash flooding. Furthermore, many streams may flood, potentially affecting larger rivers. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php