Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu May 22 2025 17:11:56 AWUS01 KWNH 221711 FFGMPD TXZ000-OKZ000-222230- Mesoscale Precipitation Discussion 0303 NWS Weather Prediction Center College Park MD 111 PM EDT Thu May 22 2025 Areas affected...Southern Oklahoma...Northern Texas.... Concerning...Heavy rainfall...Flash flooding possible Valid 221710Z - 222230Z SUMMARY...Maturing cluster thunderstorms continuing to back-build for a corridor of enhanced rainfall totals of 2-4"+. These cells may intersect recently saturated grounds to further increase potential for incidents of flash flooding through afternoon. DISCUSSION...16z surface analysis shows strong warm advection lifting primary/initial front northward mainly through the Big Country and northern Texas into the Red River Valley. This front is the leading edge of 70+ Tds toward the trailing edge of the secondary cold front that had stalled across central OK into AR.=20 Stronger easterly flow, intersection of the frontal zones appeared to be the main focus of initial convective development across south-central OK. GOES-E WV suite denotes a weak mid-level weakness across central OK as well as a subtle cyclonically curved right entrance to the 70kt 3H jet (just west enough of stronger confluence over the Mississippi River). This divergence aloft has allowed for recent uptick/expansion of convective coverage further north into central OK. With surface pressure falls further west over the Cap Rock and backed low-level WAA, a ribbon of higher theta-E air is rotating around the western side of the complex supporting a wedge of increasingly unstable air. Isallobaric influence is resulting in surface turning to then ascend along the western, fairly stationary N-S outflow boundary. Visible imagery shows the ascent into the upwind side of the cluster allowing for additional upstream redevelopment, effectively anchoring the cluster. As such, localized rainfall efficiency is increasing through the initial cluster but also expanding northward with 1.5" rates, occasionally reaching 2"/hr, though hail is contaminating the rain rate estimates, local observations are starting to press 2" totals and with an hour or more time, localized spots of 4" are becoming increasingly possible (this is in line with RRFS, ARW/ARW2 evolution which seem to have best handle on the evolution).=20 Strong downstream convergence aloft is likely to limit eastward propagation and eventually dominating cold pools should press the best convergence further south into North Texas over the next 2-3 hours, where best forcing in lower levels will continue to press westward, supporting upstream redevelopment and possible slow retrograding of the cluster with time. Unfortunately, the placement/tracks appear to be overlapping with areas that have received above normal rainfall over the last few days per AHPS.=20 As such, localized FFG are reduced to about 2"/hr and 3"/3hrs.=20 This further increases the potential for exceedance and possible further expansion and additional incidents of possible flash flooding through the afternoon. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_Uv2mqqWoUUIpk5a1jpB0LeWhTFz1VJxbQCKoEykMxIHrqNoPtV2cs3W7iu7_nWK_mYp= tdDl1QozSgkQSTV_neJ5sso$ for graphic product... ATTN...WFO...FWD...OUN...TSA... ATTN...RFC...FWR...ORN...TUA...NWC... LAT...LON 36359709 36339626 36059574 35319531 33969553=20 32939596 32539729 32829838 33369869 34039834=20 34459784 34879747 35299720 35969707=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) .