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Mesoscale Discussion 677
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   Mesoscale Discussion 0677
   NWS Storm Prediction Center Norman OK
   0914 PM CDT Fri May 22 2020

   Areas affected...eastern Oklahoma western Arkansas

   Concerning...Severe Thunderstorm Watch 206...

   Valid 230214Z - 230345Z

   The severe weather threat for Severe Thunderstorm Watch 206

   SUMMARY...Several supercells are ongoing across WW206 north of a
   remnant outflow boundary. The environment remains favorable for
   severe hail, wind gusts, as well as the possibility of a tornado or

   DISCUSSION...Recent reports of severe hail and a tornado in La Flore
   County, Oklahoma suggest that the threat for severe weather will
   continue across WW206 for a few more hours despite the loss of
   surface heating. Moist conditions, with surface dewpoints in the
   upper 60s to low 70s F are supporting MLCAPE of 2000-3000 J/kg with
   little CINH. The robust instability and sufficient vertical shear of
   40-50 kt should continue to support supercells across much of
   eastern Oklahoma and western Arkansas. The primary threat will
   likely be large hail, owing to steep mid-level lapse rates of 7-8
   C/km and the supercell structure storm mode. However, the discrete
   nature of convection, and ESRH of 100-200 m2/s2 will support
   low-level mesocyclones with the potential for a tornado or two
   through this evening.

   ..Lyons/Thompson.. 05/23/2020

   ...Please see for graphic product...


   LAT...LON   35319576 35659483 35789392 35759329 35669262 35519227
               35249221 34819247 34589283 34529335 34489406 34429485
               34469537 34549572 34799593 35169586 35319576 

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