Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 356 PM EDT Sun Sep 21 2025 Valid 00Z Mon Sep 22 2025 - 00Z Wed Sep 24 2025 ...Clusters of thunderstorms will continue through early this week across portions of the Midwest southwest through the central/southern Plains with threats of flash flooding and severe weather... ...Scattered showers and thunderstorms expected across the Southwest/California with isolated flash flooding possible... ...Above average temperatures are expected across much of the central and eastern U.S., with near to below average temperatures across the West as Summer draws to a close... Unsettled weather is expected to continue across much of the Midwest and Ohio/Tennessee Valleys west through the Mississippi Valley and into the central/southern Plains through the early part of this week. An energetic slow-moving upper-level trough and associated surface frontal/convective boundaries will help to trigger additional rounds of showers and thunderstorms, with a continuous flow of Gulf moisture helping to support heavy rainfall chances in each of the coming days. Clustering of storms along frontal/convective boundaries will bring a greater chance for repeated rounds of heavy rainfall. Into Sunday evening and night, the most likely area to see heavy rainfall and scattered instances of flash flooding is centered on the MO/KS/AR/OK border region, with a Slight Risk of Excessive Rainfall (level 2/4) now in effect. More isolated instances of flash flooding will also be possible from the Middle Mississippi Valley and portions of the central/southern Plains. A Slight Risk of severe weather (level 2/5), for mainly hail but with potential for high winds and a few tornadoes, is delineated by the Storm Prediction Center a bit farther southwest near the Red River (OK/TX border). Then, on Monday, the most likely region to see isolated flash flooding will stretch from the Ohio Valley west through the Mid-South into the Ozarks vicinity and portions of the central/southern Plains. A broad Marginal Risk (level 1/4) is in place for now, but additional areas and potentially higher levels of threat are possible with more confidence in convective trends and associated boundary locations. Severe weather could also be a threat, and Slight Risks (level 2/5) are in place in the southern/central Plains for primarily high wind and hail concerns. A more concentrated, greater threat for scattered flash flooding is already expected across the Ozarks and vicinity on Tuesday, with another Slight Risk of Excessive Rainfall (level 2/4) in effect with the potential for future upgrades. Elsewhere, daily thunderstorms can be expected across central/southern Florida as well as along the western Gulf Coast. A return of monsoonal moisture into the Desert Southwest ahead of an upper-level low over the Pacific should bring increased thunderstorm chances Sunday and Monday. Locally heavy downpours are possible, and an isolated flash flood threat will exist especially for the Colorado River Valley into central Arizona Sunday, and expanding east into western New Mexico on Monday. By Tuesday rain and thunderstorm chances will increase for parts of California, more directly related to the upper low. To the north, a cold front moving across the Northwest should continue to bring showers and thunderstorms into into portions of the northern Great Basin and Rockies. Storm chances will continue further southeastward into the central Rockies by Monday. Much of the central and eastern U.S. will continue to see above to well above average temperatures for the Fall equinox. Highs in the upper 80s to mid-90s will be common across the Southeast, Lower Mississippi Valley, and into the southern Plains/Texas once again on Monday and Tuesday, and a handful of record highs are possible especially over Texas. Temperatures in the 70s and 80s should stretch farther north across the Plains and Midwest, while a warming trend will push through the east-central and eastern U.S. on Monday and Tuesday. Meanwhile, much of the West will see temperatures around or below average on Monday, with mainly 70s in the Great Basin while the northern Rockies cools into the 60s for highs under the primary shortwave developing the upper low. Cooler air pushes into the central Rockies and High Plains by Tuesday, while the West Coast states see a warming trend into the 80s and 90s, with a few low 100s possible in the Desert Southwest. Tate/Putnam Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php