Mesoscale Discussion 0947
   NWS Storm Prediction Center Norman OK
   0634 PM CDT Sat Jun 20 2020

   Areas affected...Parts of central Nebraska

   Concerning...Severe Thunderstorm Watch 287...

   Valid 202334Z - 210130Z

   The severe weather threat for Severe Thunderstorm Watch 287
   continues.

   SUMMARY...The severe threat continues across Severe Thunderstorm
   Watch 0287. Large hail will be the primary threat, with a couple
   damaging gusts possible as well. An isolated tornado may also occur
   with the strongest storms.

   DISCUSSION...A few of the more dominant updrafts embedded within
   multicellular clusters have managed to organize into supercells over
   the past couple of hours. Some of these supercells have produced up
   to golfball sized hail and occasional strong low-level rotation,
   with a tornado reported in Blaine County in the past hour. Over 2000
   J/kg MLCAPE and 40+ knots of effective bulk shear are in place,
   suggesting that supercell structures may be sustained for at least
   the next couple of hours, as also supported by some of the recent
   high-resolution model guidance. Large hail will continue to be the
   primary threat, with a couple damaging gusts also possible,
   especially in association with supercell rear-flank downdrafts. The
   more dominant and organized supercells may also produce a tornado,
   particularly where supercells may favorably interact with
   storm-scale outflow boundaries.

   ..Squitieri/Thompson.. 06/20/2020

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

   ATTN...WFO...GID...LBF...GLD...

   LAT...LON   40390089 41160090 42110056 42810016 42809933 42499872
               42009876 41159929 40449953 40229978 40180019 40390089