Storm Prediction Center Mesoscale Discussion 941

   Mesoscale Discussion 0941
   NWS Storm Prediction Center Norman OK
   0619 PM CDT Fri May 24 2024

   Areas affected...Eastern Missouri into western Illinois

   Concerning...Severe Thunderstorm Watch 302...

   Valid 242319Z - 250115Z

   The severe weather threat for Severe Thunderstorm Watch 302
   continues.

   SUMMARY...The severe threat will continue to shift into southern
   portions of WW 302 - primarily across eastern Missouri and western
   Illinois - over the next few hours.

   DISCUSSION...A consolidated outflow boundary has become evident
   within a cluster of semi-discrete supercells north of the St. Louis
   area. MRMS data (supported by recent hail reports) indicate that the
   more intense updrafts are associated with this boundary. Easterly
   cell motions combined with steady 15-20 mph southerly inflow winds
   are resulting in a slow southward development of this boundary,
   which should act as a focus for additional thunderstorm development
   over the next couple of hours. Areas west/northwest of the St. Louis
   metro area may see an increase in thunderstorm coverage and
   intensity over the next couple of hours as forcing for ascent along
   the outflow, as well as along an approaching cold front, impinge on
   the northern fringe of a strong buoyancy axis (MLCAPE upwards of
   2500-3000 J/kg). Supportive kinematics should remain in place
   through late evening, which will continue to support the potential
   for embedded supercells along/behind the boundary with an attendant
   large hail risk (most likely between 1.0 to 1.75 inches in diameter)
   for the next 1-2 hours. Eventually, increasing forcing along the
   cold pool/front should favor upscale growth into a
   south/southeastward moving cluster down the buoyancy axis with an
   increasing wind threat.

   ..Moore.. 05/24/2024

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

   ATTN...WFO...PAH...ILX...LSX...SGF...

   LAT...LON   37819159 38189191 38469216 38759227 39059225 39389179
               39689143 39909117 39989099 39849067 39639050 39559022
               39518983 39548946 39638912 39688889 39478843 39238829
               39028835 38828852 38678890 38548927 38388948 38158966
               37838965 37668967 37438983 37358997 37269033 37309066
               37589127 37819159