Mesoscale Discussion 0853
   NWS Storm Prediction Center Norman OK
   0131 PM CDT Sat May 21 2022

   Areas affected...Extreme eastern OK...central/northern
   AR...Southeast MO...Western KY/TN

   Concerning...Severe potential...Watch possible 

   Valid 211831Z - 212030Z

   Probability of Watch Issuance...60 percent

   SUMMARY...An increase in storm coverage and intensity is expected
   later this afternoon. Watch issuance is possible.

   DISCUSSION...Storms on the southern periphery of an MCS moving
   across IL have recently shown some intensification from northeast AR
   into southeast MO. This convection has largely remained just to the
   cool side of an outflow boundary which is sagging southeastward. The
   short-term evolution of this ongoing convection remains somewhat
   uncertain. With time, however, continued heating/destabilization of
   a moist boundary layer will result in an increase in storm coverage
   and intensity along and perhaps ahead of the outflow boundary.

   A notable EML was sampled on 12Z regional soundings, and steep
   midlevel lapse rates will support MLCAPE in excess of 3000 K/kg
   along and to the warm side of the boundary. This region is on the
   southern fringe of stronger midlevel flow, with effective shear of
   25-35 kt supportive of strong multicell clusters and perhaps a
   supercell or two, given the strong instability. Large hail will
   likely be the primary initial threat, and will remain a threat with
   any more discrete convection into late this afternoon. One or more
   upscale growing clusters may evolve with time, which would pose an
   increasing damaging wind risk. 

   If/when short-term observational trends support an imminent threat
   of more than isolated severe storms, watch issuance is possible for
   some portion of the MCD area.

   ..Dean/Hart.. 05/21/2022

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

   ATTN...WFO...PAH...MEG...LZK...TSA...

   LAT...LON   35499449 35949434 36129191 36738958 37218876 36798836
               36458817 35708908 34749137 34439215 34449339 34589444
               34909477 35499449