Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Nov 05 2024 04:02:29 AWUS01 KWNH 050402 FFGMPD TXZ000-050800- Mesoscale Precipitation Discussion 1128 NWS Weather Prediction Center College Park MD 1101 PM EST Mon Nov 04 2024 Areas affected...Central Texas Concerning...Heavy rainfall...Flash flooding likely Valid 050400Z - 050800Z SUMMARY...Flash flooding likely as storms producing up to 3 inch per hour rainfall rates train over/near San Antonio and Austin. Urban flash flooding an increasing concern. DISCUSSION...A mesolow that has developed along a very slow moving cold front draped over central Texas is tapping into 30-35 kt southeasterly flow of Gulf moisture at 850 mb. This low and fronts are providing ample forcing for thunderstorms that have a history of producing 3 inch per hour rainfall rates northwest of San Antonio. The storms are aligned parallel to the I-35 corridor. As the storms grow upscale, they're backbuilding southwestward towards the Rio Grande. For the very near-term there is little pushing the front as the southeasterly flow ahead of the front is being countered by 10-20 kt NNW flow of dry air behind the front. Since these air flows are almost exactly antiparallel to each other, they're supporting the mesolow that has formed west of San Antonio. Further, they will work to keep the synoptic setup from moving too much for the next few hours. An approaching upper level shortwave over northwest Texas is gradually moving east towards the storm complex. This will increasingly work to push the complex of storms towards the east faster, which will consequently reduce the flash flooding threat with time. CAMs guidance is in good agreement in this scenario, albeit with variable timing due to poor handling of the current storms. The storms are currently over Austin and are just about into the San Antonio metro at the time of this writing. Expect a multiple-hour period of heavy rain associated with the storms. Considering the reduced FFGs associated with the urban centers, urban flash flooding is an increasing concern over the next few hours until the aforementioned shortwave moves the storms east of the I-35 corridor. Wegman ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!61EcCrLagqB-PnpGFdGXXXNvzO_9Ansvi4vY338kfBocDm8ZRg_LpXoE_OTgMGb_gFMz= nb69J93CZIYdRcgzIQtA42k$ for graphic product... ATTN...WFO...CRP...EWX...FWD...HGX... ATTN...RFC...WGRFC...NWC... LAT...LON 30859753 30659687 29829679 28959744 28619830=20 28489942 28939983 29159952 29379924 29809881=20 30539813 30819789 30829787=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) .