Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 425 PM EDT Sat Aug 21 2021 Valid 00Z Sun Aug 22 2021 - 00Z Tue Aug 24 2021 ...Hurricane Henri is forecast to make landfall over parts of Southern New England on Sunday afternoon, with a Moderate Risk of excessive rainfall starting Sunday morning... ...There is a Slight Risk of excessive rainfall over parts of the northern Mid-Atlantic/Southern New England and Tennessee/Lower Mississippi Valleys through Sunday morning... ...There is a Slight Risk of severe thunderstorms over parts of the Northern/Central Plains and the Upper/Middle Mississippi Valley from Sunday morning into Monday morning... Hurricane Henri is forecast to make landfall over parts of Southern New England on Sunday afternoon. Check with the NHCâ€s latest bulletin for the most up-to-date track and intensity of Henri. Overnight Saturday into early Sunday morning, Henri will start producing rain over parts of Southern New England. The rain will steadily increase in intensity, producing heavy rain. Therefore, the WPC has issued a Moderate Risk of excessive rainfall for the heavy rain. The heavy rain will create numerous areas of flash flooding. Furthermore, many streams may flood, potentially affecting larger rivers from Sunday morning to Monday morning. Meanwhile, tropical moisture, an old boundary, and upper-level energy will aid in producing showers and thunderstorms over the Tennessee/Lower Mississippi Valleys through Sunday morning. The showers and thunderstorms will produce heavy rain over the area. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable through Saturday morning. The excessive rainfall threat will continue over the region on Saturday into Sunday morning. A front over the Northern Rockies into the Great Basin will move eastward across the Northern/Central Plains into parts of the Upper Mississippi Valley before dissipating on Monday. The system will produce showers and thunderstorms over parts of the Intermountain West into the Great Basin on Saturday evening into Sunday. On Sunday, the showers and thunderstorms will move east across the Upper Midwest. Some of the thunderstorms may become severe. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Northern/Central Plains and the Upper/Middle Mississippi Valley from Sunday morning into Monday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Elsewhere, Red Flag Warnings and an Elevated fire weather risk remain across parts of the Great Basin through Sunday morning. Air Quality Alerts are also in effect throughout Central California and Central/Eastern Oregon due to thick wildfire smoke. Furthermore, Below-average temperatures are forecast for much of the western and north-central U.S., while muggy heat and humidity conditions remain over the Southern Plains and Lower Mississippi Valley. Heat Advisories have been issued from eastern Oklahoma to southern Louisiana, where heat indices could approach 110F. Meanwhile, Excessive Heat Warnings are in effect for parts of Louisiana and coastal Mississippi, including New Orleans, LA. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php