Mesoscale Discussion 1508
   NWS Storm Prediction Center Norman OK
   1136 AM CDT Sun Aug 16 2020

   Areas affected...Parts of central and southern Oklahoma

   Concerning...Severe potential...Watch unlikely 

   Valid 161636Z - 161830Z

   Probability of Watch Issuance...20 percent

   SUMMARY...There appears at least potential for continuing
   intensification of a cluster of ongoing storms across central
   Oklahoma, including the Oklahoma City metro area, through 2-4 PM
   CDT.  This may be accompanied by the potential for strong wind
   gusts, in addition to locally heavy rain and some hail.  It still
   seems unlikely that a severe weather watch will be needed, but
   trends will be monitored.

   DISCUSSION...Thunderstorm activity has shown some signs of
   intensification and increasing organization within a small area
   near/west of Enid.  This is near the leading/southeastern edge of
   persistent convection that appears driven by weak warm advection
   above a weak surface cold front.

   Mid/upper support for activity is unclear, but the evolution of a
   compact lower/mid tropospheric cyclonic circulation has become more
   evident, with some signs of a developing surface cold pool.  

   Convection is embedded within light (less than 10 kt) northerly
   ambient deep-layer mean flow, with shear also generally weak. 
   However, seasonably high boundary-layer moisture content to the
   south of the convection is contributing to rather large mixed-layer
   CAPE in excess of 4000 J/kg, beneath very steep mid-level lapse
   rates associated with elevated mixed-layer air.  And thermodynamic
   profiles are supportive of potentially strong downbursts and surface
   cold pool development, in addition to some hail.

   Although there is no strong signal in model output, including latest
   convection allowing guidance, for the continuation of this activity,
   with sufficient cold pool strengthening, there appears at least some
   potential for considerable upscale growth as inhibition continues to
   weak with daytime heating.  If this occurs, south-southeastward
   propagation along the frontal zone seems most probable, with
   activity possible impacting much of the Oklahoma City metro area.

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

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

   ATTN...WFO...TSA...OUN...

   LAT...LON   36059768 35739706 35299639 34919663 34329751 34549818
               34759846 35589864 36059768