Mesoscale Discussion 1512
   NWS Storm Prediction Center Norman OK
   0321 PM CDT Sun Aug 16 2020

   Areas affected...Parts of central and southern Arizona

   Concerning...Severe potential...Watch unlikely 

   Valid 162021Z - 162215Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Scattered strong thunderstorms will gradually spread off
   the higher terrain, toward the lower deserts, through 4-6 PM MST,
   posing increasing potential for strong to locally severe wind gusts.
    While it currently appears unlikely that a severe weather watch
   will be needed, trends will continue to be monitored.

   DISCUSSION...Thunderstorm development is now well underway in
   response to daytime heating and orographic forcing along much of the
   Mogollon Rim, with deepening convection also increasingly evident
   across the mountains of southeastern Arizona.  Although
   northeasterly to easterly mid-level flow appears generally weak
   (10-20 kt), above weak southerly to westerly low-level flow, it will
   contribute to a a gradual propagation of storms off the higher
   terrain, toward the lower deserts.

   The hot and deeply mixed boundary layer in lower elevations appears
   characterized by moderate CAPE on the order of 1000-2000 J/kg, which
   will provide potential for considerable thunderstorm intensification
   this afternoon.  However, convection allowing guidance, including
   recent runs of the HRRR, suggest that this may be suppressed to at
   least some extent by general mid-level subsidence, inferred from
   water vapor imagery.

   Still, given the thermodynamic profiles, at least scattered
   thunderstorm development probably will propagate off the higher
   terrain, accompanied by a risk for strong to severe surface gusts
   associated with localized downbursts and developing, southwestward
   surging surface cold pools.

   ..Kerr/Grams.. 08/16/2020

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...ABQ...EPZ...TWC...FGZ...PSR...VEF...

   LAT...LON   31701173 32631205 33051220 33721350 34321405 34401326
               34011246 33831101 33340975 33290908 32690878 32170920
               30940984 30921033 31221137 31701173