Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri May 02 2025 08:24:39 AWUS01 KWNH 020824 FFGMPD ARZ000-TXZ000-OKZ000-021430- Mesoscale Precipitation Discussion 0209 NWS Weather Prediction Center College Park MD 423 AM EDT Fri May 02 2025 Areas affected...South-Central & Eastern OK...Far Northern TX...Northern AR... Concerning...Heavy rainfall...Flash flooding likely Valid 020830Z - 021430Z SUMMARY...Fast moving, but intense cores capable of 1"/15-30 minutes and localized totals of 2-3.5" crossing saturated ground conditions likely to continue scattered flash flooding incidents through early morning. DISCUSSION...GOES-E 10.3um loop shows expanding cooling complex along the Red River in SW OK/NW TX. RADAR mosaic shows a more detail to the driving forces, with fast moving S/W almost MCV like mid-level circulation across northwest OK with a bowed arch of elevated thunderstorms angling southward with some 700mb boundary starting to activate west to east downstream of the SW into the sharpening right entrance of the 300mb jet. WV suite notes that the larger scale main vorticity center is sharpening the overall height packing and the jet is starting to accelerate to 100kts.=20 This is providing solid divergence aloft along and downstream to maintain the wave, while simultaneously continuing to keep the broad (nearly Texas wide) 40-50kt 850mb low level jet streaming northward. Upstream edge is starting to angle/veer more southwestward, potentially expanding back-building of the flanking line of the developing convective complex near a weak closing 1007/8mb surface low near KCWC. A main surface front continues to bisect the state into NW AR, though a subtle either southern stream or wake pressure trof exists south of it and south of the Red River connecting to a weak low near DEQ and southeast angling surface trof across S AR. Both are enhancing surface to boundary layer moisture convergence and isentropic ascent, eventually tapping a solid remaining well of 2000-3000 MUCAPE. While moisture flux into the boundaries continues to help pool total moisture to 1.25-1.5", the orthogonal ascent and strong convergence is increasing rates to 1.5-2"/hr.=20 As such, strong thunderstorms will continue to be maintained across much of southern OK; however,the veered eastern edge of the LLJ is starting to ascend over that southern boundary, utilizing the instability axis over central AR and breaking out thunderstorms across generally in the vicinity of I-40. Deep layer steering through much of the WAA regime may reduce some cross track/repeating in the near term, but as the shortwave approaches may flatten for increasing repeat/training environment as is ongoing across southern OK. So with increased duration, spots of 2-3.5" totals are possible along the boundaries. This alone is likely to exceed FFG in the region, but those values may have rebounded much too quickly given other soil saturation signals from NASA SPoRT. 0-40cm ratios across most of the area of the MPD are over 70-75%, though the lowest areas in central to northeast AR are still well over 60% and are above normal with the vast majority of OK, NW and W AR in the 90th percentile. As such, limited infiltration suggests that much rainfall over saturated grounds and elevated stream flows will likely continue flash flooding concerns throughout the late overnight through early morning day break.=20 Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7lNvr8BhJntG__3RUn8RJdFUjvfug-tIKslsjUN6oGC29oalLF7f7YgyIy1FGBe5pY1H= lcGZZIGPrK2ixThaOUvGSKw$ for graphic product... ATTN...WFO...FWD...LZK...MEG...OUN...SHV...TSA... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 36439462 36389273 36149122 35759043 35489020=20 35009038 34629092 34449164 34459321 34359444=20 33469635 33389821 33929857 35189715 36059633=20 =20=20=20=20=20=20=20=20=20=20=20=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .