Mesoscale Discussion 1039
   NWS Storm Prediction Center Norman OK
   0656 PM CDT Sun Jun 20 2021

   Areas affected...Southern Iowa...northern Missouri...northeast
   Kansas...and far western Illinois

   Concerning...Severe Thunderstorm Watch 294...

   Valid 202356Z - 210200Z

   The severe weather threat for Severe Thunderstorm Watch 294
   continues.

   SUMMARY...Strong to severe thunderstorms will continue to pose a
   large hail, damaging wind, and some tornado risk into the evening
   hours. Southern Iowa and northern Missouri will continue to see the
   highest risk in the next 1-2 hours.

   DISCUSSION...Discrete to semi-discrete storms continue to develop
   and mature along a surface trough and ahead of a cold front from
   southern IA to far northeast KS. A few supercells have been noted
   with 1-2 inch hail, wind damage, and a tornado reported within the
   past 2 hours from this activity. The warm sector ahead of these
   storms remains supportive of organized convection with RAP
   mesoanalysis estimating upwards of 3000 J/kg MLCAPE and roughly 40
   knots of boundary-normal effective bulk shear. While instability
   estimates may be slightly high based on the recent 00Z TOP sounding,
   the shear estimates appear valid and instability remains sufficient
   for severe convection. This includes areas of northern MO and
   southeast IA where previously cool/stable outflow has warmed into
   the low to mid 80s, minimizing surface-based and mixed-layer
   inhibition. 

   Discrete to semi-discrete storms remain likely in the near term,
   which will maintain the hail/wind and at least a low-end tornado
   threat. Storm mode may become more linear with an increasing wind
   threat through the late evening as the cold front (noted in KDMX
   reflectivity) catches up with the surface trough and increases
   forcing for ascent. A downstream watch into eastern MO and perhaps
   western IL may be needed if an organized wind threat becomes
   apparent.

   ..Moore.. 06/20/2021

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

   ATTN...WFO...ILX...LSX...DVN...DMX...EAX...TOP...

   LAT...LON   39509540 40049484 40829403 41589331 42019285 42069241
               41699177 41279111 40619068 39909084 39259134 39039208
               39079311 39009436 39139501 39509540