ZCZC SPCSWOMCD ALL ACUS11 KWNS 052055 SPC MCD 052055 AZZ000-NVZ000-CAZ000-052230- Mesoscale Discussion 1800 NWS Storm Prediction Center Norman OK 0355 PM CDT Tue Oct 05 2021 Areas affected...portions of Arizona and far southeast Nevada Concerning...Severe Thunderstorm Watch 512... Valid 052055Z - 052230Z The severe weather threat for Severe Thunderstorm Watch 512 continues. SUMMARY...Ongoing storms will continue to pose a risk for severe weather including damaging winds and large hail into this evening across WW512. A tornado is also possible, though uncertain. DISCUSSION...As of 2035 UTC, radar showed numerous strong thunderstorms ongoing across southern AZ and WW512. WV imagery shows the main upper low across southeast CA beginning to eject eastward into the southern Great Basin. Additional lift and maximum diurnal heating will help foster storm longevity and development this afternoon. Latest Hi-res guidance suggests several clusters of stronger storms are likely to evolve and move toward central Arizona over the next couple of hours. An increasing severe risk will likely accompany these storms as they move northeastward with time. Favorable buoyancy (1000-1250 J/kg of MLCAPE ) and bulk shear (40-50 kt) will continue to support a risk for damaging winds and hail, with isolated instances of significant severe possible. Low-level shear remains somewhat unfavorable for tornadoes given regional VADS and the 18z PSR sounding. However, local terrain influences, especially near the near the Mogollon Rim, and some additional backing of surface flow from height falls aloft may support a brief tornado this evening. ..Lyons.. 10/05/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GJT...TWC...FGZ...PSR...VEF... LAT...LON 32241340 32421445 32511459 36031461 36211417 36991405 36991050 36991000 36991000 32480924 32411313 32241340 NNNN