Mesoscale Discussion 1222
   NWS Storm Prediction Center Norman OK
   0912 PM CDT Fri Jul 09 2021

   Areas affected...eastern NE...southwest IA...northeast
   KS...northwest MO

   Concerning...Severe potential...Severe Thunderstorm Watch likely 

   Valid 100212Z - 100415Z

   Probability of Watch Issuance...95 percent

   SUMMARY...A severe thunderstorm watch will likely be needed by late
   evening for a severe risk expected to develop during the overnight. 
   Severe gusts will be the primary risk with the stronger storms.

   DISCUSSION...Radar mosaic shows several clusters of storms from the
   SD/NE border into parts of western NE.  Water-vapor imagery
   indicates the leading plume of large-scale ascent associated with a
   mid-level shortwave trough, is currently over the Sandhills.  The
   airmass over northeast KS northward into eastern NE/southwest IA is
   very unstable with 2500-3000 J/kg MLCAPE according to modified
   Topeka, KS and Omaha, NE 00z raobs.  The onset of an intensifying
   LLJ over the central Great Plains is being observed in KUEX and KTWX
   88D VAD data.  Models indicate the LLJ and associated warm air
   advection/isentropic lift will increase through midnight with the
   terminus of the LLJ focused over southeast NE/southwest IA and
   adjacent parts of northeast KS/northwest MO.  Current expectation is
   the ongoing strong to severe thunderstorm clusters over central NE
   will move east-southeast over the next couple of hours, with an
   associated severe hazard and move into western parts of the
   discussion area by 11pm-12am.

   ..Smith/Thompson.. 07/10/2021

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

   ATTN...WFO...DMX...EAX...OAX...TOP...GID...

   LAT...LON   42239676 41879537 41059389 39949371 39229415 38929566
               39319777 42239676