Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 258 AM EDT Wed Sep 24 2025 Valid 12Z Wed Sep 24 2025 - 12Z Fri Sep 26 2025 ...Widespread thunderstorms continue ahead of a frontal system stretching from the Northeast/Great Lakes to the southern Plains bringing a flash flood threat... ...Showers and thunderstorms return to the Southwest Thursday with a risk for flash flooding... ...Cooler temperatures expected in the south-Central U.S. while the northern tier heats up... Widespread thunderstorms will continue ahead of an upper-trough and associated surface cold front pushing eastward from the central to eastern U.S. the next couple of days. On Wednesday, storms can be expected from the Northeast and Lower Great Lakes southwest through the Appalachians, Ohio/Tennessee Valleys, the Middle/Lower Mississippi Valley, and the southern Plains. The greatest chance for heavier downpours and potential repeated rounds of storms will be across the Upper Ohio Valley southwest into the central Tennessee Valley, where a Slight Risk of Excessive Rainfall (level 2/4) is in effect for the threat of scattered flash flooding. More isolated instances of flash flooding can be expected broadly from the Ohio Valley southwest through the Lower Mississippi Valley and to the western Gulf Coast/portions of Texas. Then, on Thursday, as the front continues eastward, the focus for storms will stretch from the Northeast south along the East Coast and through the Appalachians into the Southeast, as well as southern Texas. While moderate to locally heavy rainfall can be expected, drier antecedent conditions through much of this region will keep the flash flood threat isolated, with some instances possible for portions of southern New England/the greater NYC area as well as the southern Appalachians. Some damaging winds gusts will also be possible with these storms over the next couple of days. Daily thunderstorms can also be expected across the Florida peninsula. An upper-low that has been meandering along the West Coast the last few days will finally start to shift eastward Wednesday , bringing another round of thunderstorms to the central California Coast with an isolated threat for flash flooding. On Thursday, the system will begin to tap into very moist air over Mexico and draw it northward, bringing thunderstorm chances back to the Southwest as well as portions of the Great Basin/Sierra. Locally heavy downpours are expected, with a Slight Risk of Excessive Rainfall across portions of eastern Arizona and far western New Mexico where the highest moisture will be concentrated. Scattered instances of flash flooding will be possible especially for terrain sensitive areas such as burn scars, as well as for urban areas. More isolated instances of flash flooding will be possible elsewhere through the region. Much of the country will continue to see above average temperatures the next couple of days, with some of the greatest anomalies across the northern tier. Most highs from the Pacific Northwest east through the northern Rockies and Plains will be into the 80s Wednesday and Thursday, with 70s in the Upper Midwest. A system approaching the Pacific Northwest Thursday will bring cooler temperatures in the 60s and 70s to the coast and urban corridor while conditions remain hot, dry, and windy in the interior, prompting a Critical Risk of Fire Weather from the Storm Prediction Center. Much of the West will also be above average, with highs in the 70s and 80s for the Great Basin and 90s to mid-100s for the Desert Southwest. The upper-low over California will keep highs around or below average, with 80s inland and 70s along the cost. Highs will also be above average along the East Coast, with 70s across the Northeast, 80s in the Mid-Atlantic, and 90s from the Carolinas to Florida. Meanwhile, temperatures will be well below average behind the cold front over portions of the central U.S. Wednesday, with highs mainly in the 70s from the central Plains east to the Middle Mississippi/Ohio Valleys and southward into the southern Plains as well as portions of Texas. Temperatures will moderate some Thursday. After highs into the 90s Wednesday for the Southeast and Gulf Coast, the cold front will drop highs for much of the region into the 80s Thursday. Putnam Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php