Mesoscale Discussion 1285
   NWS Storm Prediction Center Norman OK
   0748 PM CDT Sun Jul 19 2020

   Areas affected...Northeast Wyoming...Southwest South
   Dakota...Western Nebraska...Far Northeast Colorado...Far Northwest
   Kansas

   Concerning...Severe Thunderstorm Watch 387...

   Valid 200048Z - 200245Z

   The severe weather threat for Severe Thunderstorm Watch 387
   continues.

   SUMMARY...A severe threat will likely continue through the mid to
   late evening across much of the central High Plains. The main
   threats will be wind damage and isolated large hail. An isolated
   tornado threat will also be possible for another hour or so.

   DISCUSSION...The latest surface analysis shows a 1006 mb low over
   southeast Wyoming with surface winds backed to the east and
   southeast across much of the central High Plains. A moist airmass is
   in place across western Kansas and western Nebraska where surface
   dewpoints are mostly in the 60s F. This is contributing to a
   corridor of moderate instability from far southwest Nebraska
   extending north-northwestward into northeast Wyoming. Strong to
   severe thunderstorms are ongoing along the western edge of moderate
   instability. This activity will gradually move eastward across this
   instability corridor from mid to late evening. In addition, the
   Thedford, Nebraska WSR-88D VWP shows 0-6 km shear of 45 to 50 kt.
   The wind profile has directional shear in the low-levels with speed
   shear in the mid-levels. This combined with steep mid-level lapse
   rates will be favorable for supercells with isolated large hail.
   Supercells may also produce damaging wind gusts and could be
   associated with a tornado threat for another hour or so. As cell
   mergers occur and line segments organize, the wind damage threat may
   increase later this evening.

   ..Broyles.. 07/20/2020

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

   ATTN...WFO...LBF...UNR...GLD...BOU...CYS...

   LAT...LON   44170513 43370501 43000443 41730338 40410296 39820256
               39640168 39710061 40130035 41050027 42050043 42910145
               44230295 44810475 44170513