Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 425 PM EDT Wed Aug 28 2024 Valid 00Z Thu Aug 29 2024 - 00Z Sat Aug 31 2024 ...Above average heat expected to linger across the Ohio and Tennessee Valleys through Friday... ...Severe thunderstorms and flash flooding possible across the Upper Midwest, central Plains, Mid-Atlantic, and central Gulf Coast Thursday through early Friday... Record-setting high temperatures over the Mid-Atlantic should abate after today, but the warm temperatures in the Ohio and Tennessee Valleys should persist through Friday with highs in the mid-to-upper 90s across much of the area. Above average overnight low temperatures will provide little relief, lows will likely stay in the 70s for much of the region. Precipitation chances with the approaching front should quell the temperatures going into the weekend. A cold front extending from an area of low pressure in Canada will move eastward across the middle of the country over the next couple days and bring a risk for severe thuderstorms to much of the Upper Midwest. The Storm Prediction Center has issued a Slight Risk of Severe Thunderstorms (level 2/5) for Thursday, scattered severe thunderstorms are expected to be organized and there may be embedded supercells that may contain damaging winds, large hail, and a few tornadoes. Meanwhile, a frontal boundary will sag south into the Mid-Atlantic, where thunderstorms may contain some gusty winds and heavy rain may lead to isolated to scattered instances of flash flooding. A Slight Risk of Excessive Rainfall (level 2/4) is in effect Thursday across the Mid-Atlantic where 2-4 inches of rainfall will be possible in any locally strong thunderstorms. As the frontal system progresses, the risk for isolated instances of flash flooding will shift east on Friday, and there is a Marginal Risk of Excessive Rainfall (level 1/4) from the eastern Great Lakes through the Middle Mississippi Valley to the southern Plains. Separate from the frontal system across the norther tier of the country, enhanced moisture around the Gulf Coast has increased the threat for heavy rain and flooding, so a Slight Risk of Excessive Rainfall (level 2/4) has been issued for the east Texas Gulf Coast for Thursday and Friday. Across the rest of the country, a general cooldown is expected behind the cold front across the north-central U.S. and high temperatures should be generally in the middle 80s. Much of the Southeast should be warm and humid with commonplace high temperatures in the middle 90s. The western U.S. should be warm with above average temperatures for most of the region. Wilder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php