Mesoscale Discussion 1572
   NWS Storm Prediction Center Norman OK
   0300 PM CDT Tue Aug 25 2020

   Areas affected...Parts of central into southern Arizona

   Concerning...Severe potential...Watch unlikely 

   Valid 252000Z - 252230Z

   Probability of Watch Issuance...5 percent

   SUMMARY...A damaging gust or two may accompany the heavier storm
   cores. The isolated nature of the severe threat precludes a WW
   issuance.

   DISCUSSION...Strong surface heating has resulted in temperatures
   exceeding 100F in several locales across central and southern
   Arizona, with pulse-cellular convection underway. The high
   temperatures/strong heating are contributing to a deepening boundary
   layer, mixing up to 600 mb in spots. Precipitable water values
   exceeding 1.25 inches in spots, along with 8-9 C/km low-level lapse
   rates, may result in strong evaporative cooling and associated
   downdrafts with the stronger storms, with a couple damaging gusts
   possible. 12Z HREF and the last few runs of the HRRR suggest that
   some clustering of stronger storms may result later this afternoon,
   but will most likely transpire just south of the international
   border. As such, the severe threat is expected to be rather isolated
   in nature, and a WW issuance is not expected.

   ..Squitieri/Bunting.. 08/25/2020

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

   ATTN...WFO...TWC...FGZ...PSR...

   LAT...LON   32201394 33781348 34651313 35041225 35121136 34781023
               34140934 33730908 33340970 32721059 32071090 31611122
               31451155 32201394