Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Dec 26 2024 14:01:54 AWUS01 KWNH 261401 FFGMPD TXZ000-OKZ000-261930- Mesoscale Precipitation Discussion 1191 NWS Weather Prediction Center College Park MD 901 AM EST Thu Dec 26 2024 Areas affected...Northern Texas...Southeastern Oklahoma... Concerning...Heavy rainfall...Flash flooding possible Valid 261400Z - 261930Z SUMMARY...Warm advective wing of highly dynamic cyclogenesis already breaking out elevated convection. Continued increasing moisture flux and slow instability advection to increase rainfall rates to 1.5"/hr crossing areas of recent heavy rainfall.=20 Short-term training elements pose risk of localized possible flash flooding. DISCUSSION...A very strong and sharp shortwave can be seen moving out of the Texas Panhandle into western OK. A strong digging 100kt jet parallel to the Front Range of the Rockies decelerates sharply before rounding a slowly negatively tilting trof across the Big country then rapidly accelerating into 100-105kt SSW jet across the MOKSAROK placing much of northeast Texas into a very dynamic/favorable upper-level pattern for rapid evacuation and strengthening low level flow...as noted by transverse banded activity across the Big Country. Deep layer moisture has been limited to the Gulf; but recent CIRA LPW suite denotes that the strengthening low level jet in response to the height-falls is advecting increasing moisture and higher theta-E across central TX toward the region. The nose of the MUCAPE axis has recently nudged into the area of ascent with 500 to 750 J/kg being analyzed; and as such, recent convective towers have been forming along the northeast edge of the Hill country with active increasing lightning detected.=20 Strong WAA pattern from the SW through 700-500mb, indicates the strong steering pattern; but with the low level moisture and WAA response, redevelopment along the effective boundary slowly lifting northeastward across N TX, will allow for some convective elements to have a training profile. This training/back-building potential is likely to be the main key/driving factor to localized flash flooding as well as crossing areas recently saturated from prior rainfall two days ago. NASA SPoRT 0-40cm denotes a sharp gradient of soil saturation along I-35, becoming 50-65% saturated toward northeast TX; however, AHPS 7 day anomaly shows those deeper saturation may extend a county or two further west; increasing the potential to intersect with the heavy rainfall. Cells are likely to be a bit more moisture starved given limited mid to upper level moisture and the training is likely to help over come it. However, the strength of ascent and focused convergence in banded convective lines may allow for .5"/hr to increase to 1.5"/hr throughout the late morning into early afternoon hours with increased moisture flux. As such, streaks of 1-3" totals are probable through the morning with slow northeastward expansion of the WAA. This places the rates and totals near or slightly above the lowered FFG values across the area of concern into SE OK; so localized exceedance is possible with increased potential in and around the urban DFW corridor.=20=20 As such, flash flooding is considered possible. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7-lwxPQ-ppsZeC5-MLk-uR9jROzDzUapNNWF7iakQfIoO1oPbEoLcDJr0cI4ugbnYljw= Txlo75z-qsOIWKVuiuEnTVY$ for graphic product... ATTN...WFO...FWD...OUN...SHV...TSA... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 34969605 34879539 34399470 33709458 32999468=20 32499532 32069612 31599769 31689832 32309881=20 33299863 34219764 34679693=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) .