Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Sep 13 2025 19:40:10 AWUS01 KWNH 131940 FFGMPD TXZ000-NMZ000-AZZ000-140115- Mesoscale Precipitation Discussion 1081 NWS Weather Prediction Center College Park MD 339 PM EDT Sat Sep 13 2025 Areas affected...New Mexico...Far Southeast Arizona...Portions of Western Texas Panhandle... Concerning...Heavy rainfall...Flash flooding possible Valid 131940Z - 140115Z SUMMARY...Deep layer available moisture and sufficiently unstable environment to support storms capable of up to 1"/hr. Some favorable development lines and deep layer flow may result in repeating tracks and localized spots of 2", resulting in possible widely scattered, but localized flash flooding throughout the afternoon/evening. DISCUSSION...Core of strong large scale trof continues to slowly lift northeastward across southern UT with solid downstream height-falls supporting broad scale ascent pattern allowing for increased overall convective coverage today. The deep layer sub-tropical moisture has further angled SW out of the northern Mexican Plateau into southern New Mexico, though the western gradient remains across far SE AZ into north-central NM. However, this is shifting eastward with strong, well defined dry slot (700-500mb CIRA LPW denotes this very well) off the San Francisco Plateau through the Four Corners. This is overall narrowing the moisture plume, but also increasing southeasterly upslope flow and surge of Gulf of America moisture through the Rio Grande/Pecos River Valley into the NM High Plains.=20=20 Solid clear skies, particularly west of yesterday's leading height-fall/pressure trough currently seen through the TX Panhandle back southwest through the Davis Mountains and western TX panhandle. As such, surface temperatures have supported a solid increase in instability fields, slightly higher further southward given deeper overall moisture (Tds in the low 60s) and good lapse rates, though still with ample deep layer moisture to support efficient rainfall production.=20 At this time, SW to NE linear features are expanding in convective anvils and embedded overshooting tops across far SE AZ and SW and west-central NM. Orientation is parallel to the mean flow so some repeating tracks are probable. However, cell motions are above normal limiting overall duration of any internal core, still quick burst of .5" totals and 1-1.25"/hr totals could be possible with said repeating. Hard ground conditions/naturally lower FFG values suggest localized exceedence is possible resulting in possible localized flash flooding. As the afternoon progresses, SSW to NNE 70 jet streak will continue to lift north across CO and increasing diffluence will further expand already sufficient divergence area, for further uptick in convective coverage with expanding clusters across central NM into the High Plains. The further acceleration of deeper moisture should also increase rainfall efficiency toward late evening (after 00z) with rates of 1-1.5"/hr becoming possible. An update to the MPD may be required as these clusters grow upscale later this evening. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7G_ir-FoXeVBA-9DkzF9snX7eZdnaBBt8lbX58RydRTFJF_8RvGni2LJH5Ii-J6_MBLD= kl_Jk2R6QhoX1JqhqyPtqM4$ for graphic product... ATTN...WFO...ABQ...EPZ...MAF...TWC... ATTN...RFC...FWR...STR...TUA...NWC... LAT...LON 36870499 36840389 36320321 35130314 33120322=20 32430404 31240490 31010565 31700679 31660792=20 31230809 31180863 31220974 31311045 32371063=20 33370940 34460826 35490738 36530617=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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .