Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Aug 07 2023 21:04:38 AWUS01 KWNH 072104 FFGMPD NMZ000-AZZ000-080300- Mesoscale Precipitation Discussion 0884 NWS Weather Prediction Center College Park MD 503 PM EDT Mon Aug 07 2023 Areas affected...Southeast Arizona...Southwest New Mexico... Concerning...Heavy rainfall...Flash flooding likely Valid 072105Z - 080300Z SUMMARY...Solid Return moisture flow out of the Sea of Cortez and very unstable environment should allow for efficient rainfall with rates of 2"/hr and localized totals of 2-2.5" pose possible scattered instances of flash flooding. DISCUSSION...Broad scale dual GOES-E and W WV suite depicts a confluent upper-level jet structure across S CO/N NM with broad anticyclonic return flow eminating from Northwest Mexico. LPW analysis suggest slug of enhanced subtropical moisture channeled northward as a response to T.S. Eugene and it's parent tropical wave. Broad slantwise isentropic/upslope ascent has brought a core of 1.5-1.75" total PWats into SE AZ, with mid-level stream into the right entrance region of the jet across central NM. Full heating and some low level moisture convergence along the northeast side of the anticyclonic return flow has lead to rapid destabilization across SE AZ with broad updrafts and downdrafts feeding off 3500-4000 J/kg of MLCAPE. Given available moisture and isallobaric inflow response, very efficient rainfall production (with some hail generation) has been estimated from 2-2.5"/hr. Some modest mid-level dry air is producing some weak outflow, which suggests slow eastward and southward propagation. Given duration, spots of 2-3" are possible and likely to induce other instances of flash flooding through the late afternoon and evening especially across SE AZ/SW NM. Further north, RADAR and visible imagery shows solid line of cooler tops and enhanced reflectivitiy at the apex of the isentropic ascent into the right entrance to the jet. LPW shows nose of enhanced moisture bleeds into Cantron/Cibola counties but remains moderately dry east of that axis. Additionally, sub-cloud dew point depressions are sizable given Tds in the 30s and 40s with 80s to 90s temps. Expect that all but the farthest southwest cells are capable of heavy rainfall. However, orientation of the band is fairly parallel to the deeper layer flow, suggesting some training is possible. If leading cells can locally saturate the sub-cloud environment, upstream cells may have a low risk of sufficient rainfall for perhaps a very isolated flooding concern (mainly given harder ground conditions), but this is considered more unlikely than likely but remains a non-zero risk. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-IhsE_kjVXiXlLYiL7Yr4Hcwe1mtO7MX--XDR29TDde6buhGdkSsIevwN3m5nO0g8TRb= FwTruCdgCTflSfrsdTHCdFM$ for graphic product... ATTN...WFO...ABQ...EPZ...FGZ...TWC... ATTN...RFC...CBRFC...WGRFC...NWC... LAT...LON 34990793 34920608 34440567 33970594 33100786=20 32250818 31270829 31240911 31211015 31421110=20 33121013 34380924=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) .