Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Sep 24 2025 03:08:05 AWUS01 KWNH 240306 FFGMPD ARZ000-TXZ000-OKZ000-240900- Mesoscale Precipitation Discussion 1128 NWS Weather Prediction Center College Park MD 1105 PM EDT Tue Sep 23 2025 Areas affected...Much of Arkansas...Southeast Oklahoma...Far Northeast Texas... Concerning...Heavy rainfall...Flash flooding likely Valid 240310Z - 240900Z SUMMARY...Developing thunderstorms capable of 1.5-1.75"/hr, likely to repeat through areas of saturated soils with scattered pockets of additional 2-4" totals, likely resulting in new incidents of or continue ongoing flash flooding through the overnight period. DISCUSSION...GOES-E WV suite depicts broad core of deep upper low well upstream over the Colorado High Plains dropping southeast; while a broad elongated mid-level dry slot across centered along the KS/OK border extending through MO into the Midwest. This has resulted in a regionally flat mid-level shear axis along and north of the area of concern. The warm conveyor belt of enhanced deep, overlapping moisture axis remains very active with large clusters of cold cirrus shield mainly over SW AR, with only a few overshooting tops dotting along the moisture axis into far SW TN/NW MS. As such, the surface to low level environment remains aligned with the warm conveyor. A weak surface to 850mb low is exiting NE OK into the Ozark Plateau, with upstream cold advection occurring across E OK. This sharpening has increased convergence along a remaining axis of 2000 J/kg of MLCAPE supporting a secondary increase in convective vigor and coverage upstream of the initial band that is slowly eroding and becoming more scattered in nature across central AR toward the TN/MS line. With additional development upstream of areas already flooded across NW AR and E OK, additional 2-3" totals due to 1.5"/hr rates is likely to maintain ongoing flooding situations. However, further southwest, the reservoir of remaining unstable/unmixed air across the Red River Valley has a bit broader instability axis to work with and thunderstorms are just that bit stronger with tops below -70C. 500-1000mb thickness depicts a broadening divergence suggesting weakening propagation vectors, slowly backing upstream to suggest some back-building may occur over the coming hours. This clustering/expansion will increase mergers, short-term training across far SE OK/SW AR into far northern TX. Slightly higher moisture flux convergence will also support rates of 1.75"/hr, occasionally and locally peaking over 2"/hr. As such spots of 2-4" are becoming more likely. The area has not seen the heavier rain over the last week or so, as further north, so grounds are a bit more accepting of these higher totals; given FFG values of 2-3"/hr or 3-4"/3hrs, suggesting incidents of flash flooding will still be more scattered in nature/coverage than further north, but a few incidents are still likely (with the only exception near Montague to Grayson county, TX). Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!44jtdujgBJ1BR-OWzjRm12Isx_zZyOiDd0-tIodVhFT_r9EPUHV_w59ZlRPmW7XyDPW3= j0Q9impEEnprN8J13F1okbo$ for graphic product... ATTN...WFO...FWD...LZK...OUN...SHV...TSA... ATTN...RFC...FWR...ORN...TUA...NWC... LAT...LON 36099332 35609171 34979117 34089141 33419292=20 33149393 33009526 33099734 33709764 34529643=20 35339522 36079432=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .