Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jul 24 2024 19:36:34 AWUS01 KWNH 241936 FFGMPD NMZ000-AZZ000-UTZ000-NVZ000-CAZ000-250135- Mesoscale Precipitation Discussion 0719 NWS Weather Prediction Center College Park MD 335 PM EDT Wed Jul 24 2024 Areas affected...Southwest U.S. Concerning...Heavy rainfall...Flash flooding possible Valid 241935Z - 250135Z SUMMARY...Scattered areas of monsoonal showers and thunderstorms are expected to develop today across the Southwest, including much of southern and western AZ, far eastern CA, southern NV and southwest UT. Some localized concerns for flash flooding will exist over any burn scar areas along with localized slot canyons and the normally dry washes. DISCUSSION...The latest GOES-W Day Cloud Phase RGB satellite imagery shows the remnants of an MCV situated over southern NV, along with cloud cover and some weak vort energy stretched out across northwest AZ. Strong diurnal heating continues across the region, and gradually the uptick in boundary layer instability coupled with some of the cloud-induced differential heating boundaries should encourage at least scattered areas of showers and thunderstorms to develop. Additional orographic ascent/forcing near the higher terrain will also contribute to a gradually expanding threat of monsoonal convection over the next several hours. SBCAPE values have increased to 1000 to 2000 J/kg locally and an additional uptick in diurnally-driven instability is expected over the next several hours. Convection that initiates along the Mogollon Rim is expected to be in a position to move off the terrain down to southwest by later this afternoon, and with a rather strong degree of surface-based instability, some of this convection may attain at least some organization and especially into areas of south-central AZ where somewhat stronger mid-level shear is noted. Some rainfall rates with the stronger convective cells today may reach 1 to 2 inches/hour, and some localized 2 to 4 inch rainfall totals may be possible where any of these cells tend to become more focused. Some isolated to widely scattered instances of flash flooding will be possible as convective initiates and gradually expands in coverage. The normally dry washes, any burn scar locations, and the localized slot canyons locations will again be the more vulnerable areas for flash flooding impacts. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8qMHnB-qy5j4GA7UT_QxRc_j7VfaBjzfr6sFST8P39HcGRBxDgkQ7E-wA6yvoGdm9F8W= _84-cu0plyD4nQmigru-gFE$ for graphic product... ATTN...WFO...ABQ...EPZ...FGZ...LKN...PSR...SLC...TWC...VEF... ATTN...RFC...CBRFC...CNRFC...NWC... LAT...LON 38761316 37891186 35911134 35021057 33660889=20 31960901 31311083 31901293 33261373 34081435=20 34931554 37071633 38371526=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) .