Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat May 27 2023 22:47:08 AWUS01 KWNH 272247 FFGMPD TXZ000-NMZ000-280400- Mesoscale Precipitation Discussion 0360 NWS Weather Prediction Center College Park MD 646 PM EDT Sat May 27 2023 Areas affected...East Central NM...Cap Rock & Northern Permian Basin of West TX... Concerning...Heavy rainfall...Flash flooding possible Valid 272245Z - 280400Z SUMMARY...Developing clusters of thunderstorms at nose of moisture channel may grow upscale and turn southeast crossing areas of lower FFG posing possible aggravation of flooding this evening. DISCUSSION...Stronger surge of southwesterly flow originating in the sub-tropical Pacific has over-topped the shallower cT airmass across the desert Southwest/Mexican Plateau providing broad scale ascent and up-slope flow off the Southern High Plains. This has resulted in strong moisture flux convergence along a sharp dry line in proximity of the Sacramento Range into the southern Sangre de Cristo Range of Northeast NM. Stronger ascent to the south across W TX has filtered northward a bit into Chaves county with only scattered cells trying to enhance into San Miguel/Guadelupe counties as noted in GOES-E visible and lightning detection. The Chaves complex has been developing at the nose of a narrow low-level return flow channel enhanced by surface meso-high/ridge over the Cap Rock from this morning's MCS. Surface to 850mb of 15-20kts is more focused directed from the southeast, with RAP analysis denoting a pocket of higher 925-850mb moisture (northeast gradient on the sfc-850mb LPW moisture plume). While stronger inflow is likely to result in faster propagation, the enhanced flux convergence will also support higher rainfall efficiency.=20 While not as efficient has last night's complex, there will sub-hourly totals of 1-2" and overall totals to 2".=20=20 Deep layer flow appears to be supporting a ESE trajectory of the expanding complex of thunderstorms, though 500-1000mb thickness suggest a further turn toward the southeast is probable nearing the ridge axis as the complex moves into Texas. Still, this should overlap with areas affected significantly in E NM and W TX where hourly FFG values are between .75-1.5" with much of area below 2"/3hrs. Hi-Res CAMs have been poor in handling the region due to the small scale complexity left by the old MCS/assimilation into current runs, though 12z ARW2 seems to have best handling on the evolution there is not sufficient confidence to declare these clusters will track through the saturated area with certainty and as such, flash flooding is only considered possible, but if northern cells continue to expand that risk further increases given southeast turn toward the lower FFG values. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_DSNmCaSCu9hgmn7rnWyh8OCI2v-t6UBvDO972M7Gjv6jZwfItmNcniWySGqk30OKgnc= bmJib1H42g_iI2CMhwyRsuQ$ for graphic product... ATTN...WFO...ABQ...AMA...LUB...MAF... ATTN...RFC...ABRFC...WGRFC...NWC... LAT...LON 35730403 35450344 35410317 35370261 35110206=20 34520131 33570088 32560125 32680243 33420319=20 33970389 34220425 34470474 34880507 35330515=20 35640471=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) .