Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Aug 12 2023 17:46:37 AWUS01 KWNH 121746 FFGMPD TXZ000-OKZ000-KSZ000-COZ000-NMZ000-122342- Mesoscale Precipitation Discussion 0911 NWS Weather Prediction Center College Park MD 145 PM EDT Sat Aug 12 2023 Areas affected...Central and Northern NM...South-Central to Southeast CO...Far Southwest KS...Western OK Panhandle Concerning...Heavy rainfall...Flash flooding likely Valid 121742Z - 122342Z SUMMARY...Showers and thunderstorms will be developing and expanding in coverage over the next several hours. Slow cell-motions and heavy rainfall rates are expected to cause some areas of flash flooding. DISCUSSION...The latest GOES-16 IR and GeoColor satellite imagery shows areas of showers and thunderstorms developing and tending to expand in coverage across areas of northern NM near the Sangre De Cristo mountains and northward across areas of south-central and eastern CO as deep layer southerly flow transports a well-defined axis of monsoonal moisture northward around the western periphery of the subtropical ridge over the southern Plains. Embedded within this southerly flow are some weak vorts, and actually the visible satellite imagery shows a well-defined MCV lifting north currently across central NM. Strong boundary layer heating is underway across areas of northeast NM and southeast CO, and the diurnally-driven destabilization of this airmass coupled with moist low-level flow over the southern High Plains in close proximity to a front will allow for the convection that is initiating over the higher terrain now to gradually expand in coverage off to the east going through the afternoon hours. MLCAPE values are already on the order of 500 to 1000 J/kg over northeast NM to the east of the Sangre De Cristo range, but these values will be increasing over the next few hours, and the low-level upslope flow into the terrain and aforementioned vort energy lifting north will be key factors in allowing convection to organize and expand in coverage over the next several hours. PWs across the region are fairly high with the deep monsoonal fetch, with values running as high as 1.5 standard deviations above normal. The CIRA-ALPW data shows the 700/500mb layer in particular is quite moist and this should favor rather efficient rainfall processes for enhanced rainfall rates that could reach as high as 2 inches/hour with the stronger storms. The cells will also tend to be slow-moving in nature, and some localized repeating of cells over the same area will be possible. As a result, some of the storm totals will likely be excessive, with the HREF guidance supporting locally as much as 3 to 5 inches of rain. At least scattered instances of flash flooding will be likely as a result, and this will include the Sangre De Cristo range where there are some notable burn scar sensitivities. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8G8zbjCAQLfE8PdlkK588iCyXkNs31VdN78_6GYvPdUTEvFSpp33vTaFnSBZDeGBpsQ_= f4bbIaCkfFvcgCR55PThge0$ for graphic product... ATTN...WFO...ABQ...AMA...BOU...DDC...GLD...PUB... ATTN...RFC...ABRFC...WGRFC...NWC... LAT...LON 38790298 38450178 37660125 36820143 36420207=20 36170313 35930387 35640447 35350502 35500576=20 36110579 36640569 37650528 38570431=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) .