Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Oct 27 2023 22:09:46 AWUS01 KWNH 272209 FFGMPD LAZ000-ARZ000-TXZ000-OKZ000-280407- Mesoscale Precipitation Discussion 1164 NWS Weather Prediction Center College Park MD 608 PM EDT Fri Oct 27 2023 Areas affected...Portions of North-Central and Northeast Texas Concerning...Heavy rainfall...Flash flooding possible Valid 272207Z - 280407Z SUMMARY...A strong but stalling out cold front is running into a tropical air mass ahead of the front characterized by 70s dew points. This will develop an axis of heavy rain along the front, likely to be located just south and east of Dallas, along which slow-moving and training storms will locally increase the flash flooding threat. DISCUSSION...Latest radar and satellite imagery shows increasing coverage of convection along a front moving across the Dallas-Fort Worth Metroplex this evening. Cool, dry air characterized by dew points in the 50s is colliding with a tropical air mass with dew points well into the 70s. This clash of very different air masses will be the focal point for the scattered showers and thunderstorms that have developed so far to organize along and south/east of the front. The storms will be aided by increasing influence of the right entrance region of a strong jet over the central Plains, and a much more subtle 700 mb vort max that will track north out of the northwestern Gulf and into northcentral and northeastern TX. The high moisture content of the air, with PWATs around 2 inches, with MLCAPE values between 2,000 and 3,000 J/kg will provide ample moisture and instability for repeating showers and storms to feed on. Corfidi vectors of 10 kt out of the west will help tie the storms to the front. Since the front is forecast to stall out, this will allow the storms to repeat over the same areas, increasing the flash flooding threat, especially in the maroon hatched area. There remains some uncertainty as to where the strongest storms will develop, albeit the maroon hatched area is most likely. A small deviation north and west would move the training storms both over Dallas and over areas that have been much harder hit by heavy rains in recent days. This scenario would result in significantly more widespread and impactful flash flooding, so the situation will continue to be closely monitored. For the remainder of the pink area highlighted, more widely scattered and faster-moving storms should keep any resultant flash flooding more isolated, so the threat is not as high. However, if a stronger storm moves over a more sensitive or urbanized area, flash flooding will be possible. Wegman ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9iZ3amhYeGKBQG7-lYFZmq-XiyoUrFTjgISc9-uHed-FbLbb06cmpyKz_gHt9NtJ5q_G= o3v77NUxtTSU2UqfAZMim5k$ for graphic product... ATTN...WFO...EWX...FWD...HGX...SHV...SJT... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 33819453 33089361 31709452 30239628 29239811=20 29479979 31499900 32189769 32809686 33309589=20 33309589=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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .