Mesoscale Discussion 0471
   NWS Storm Prediction Center Norman OK
   0640 PM CDT Fri Apr 24 2020

   Areas affected...Eastern Oklahoma and western/central Arkansas

   Concerning...Severe Thunderstorm Watch 145...

   Valid 242340Z - 250145Z

   The severe weather threat for Severe Thunderstorm Watch 145
   continues.

   SUMMARY...The greatest hail threat within WW 145 will exist with
   discrete activity in eastern OK into western Arkansas. The threat
   for damaging/severe wind gusts will increase as storms organize
   linearly along the advancing cold front. Deep-layer shear and
   upper-level forcing will remain favorable, but buoyancy will
   decrease this evening. A downstream severe thunderstorm watch may be
   needed for western/central Arkansas should convective trends
   warrant.

   DISCUSSION...A discrete supercell within Haskell/Sequoyah Counties
   in Oklahoma will likely be the source of the greatest hail threat
   (1-2 inches possible) during the next 1-2 hours. To the west of this
   cell, linear development has increased along the cold front. This
   line of thunderstorms is likely to continue eastward for some time
   given the favorable large-scale ascent moving across the region.
   With time, storms along the front are likely to overtake any
   discrete activity out ahead of it where the threats will primarily
   become damaging/severe wind gusts and marginally severe hail. The
   main uncertainty is how severe the storms along the front will be as
   they progress into western/central Arkansas over the next few hours.
   Upper-level forcing and effective shear (40-50 kts) will remain
   favorable; however, buoyancy will tend to decrease with time as the
   boundary layer cools. MLCAPE of 500-1000 J/kg will be possible this
   evening. A downstream severe thunderstorm watch may be needed in
   portions of central Arkansas. Convective trends will be monitored.

   ..Wendt.. 04/24/2020

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

   ATTN...WFO...LZK...SGF...TSA...OUN...

   LAT...LON   36489567 36849507 36649381 36249301 35589252 34939261
               34599325 34559424 34619498 34899577 35349608 35829612
               36489567