Storm Prediction Center Mesoscale Discussion 911

   Mesoscale Discussion 0911
   NWS Storm Prediction Center Norman OK
   0620 PM CDT Sat May 30 2026

   Areas affected...parts of western Nebraska and South
   Dakota...northeast Colorado...and extreme eastern Wyoming

   Concerning...Severe Thunderstorm Watch 252...

   Valid 302320Z - 310045Z

   The severe weather threat for Severe Thunderstorm Watch 252
   continues.

   SUMMARY...Thunderstorms will continue to develop this evening across
   Severe Thunderstorm Watch #252. Isolated large hail and strong winds
   will remain possible across the watch.

   DISCUSSION...Thunderstorms continue to develop and grow upscale into
   north-south linear clusters this afternoon/evening to the northeast
   of a negatively tilted mid-level trough moving across north-central
   Colorado into eastern Wyoming.

   The overall environment remains favorable for strong to severe
   thunderstorms, with MUCAPE in the 1000-2000 J/kg range, with
   deep-layer shear on the order of 30 knots. However, deep-layer shear
   is mostly parallel to the initiating boundaries, which will favor
   seeding of downstream updrafts, acting as an overall check on
   thunderstorm intensity. Thus, despite overall an environment that
   would support a sustained hail and wind threat this evening, the
   most likely scenario is for any severe hail or wind to occur on an
   isolated basis with the strongest of updraft cores as the overall
   complex moves east into the central/northern Plains.

   The activity should weaken later this evening with the loss of
   diurnal heating.

   ..Marsh.. 05/30/2026

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

   ATTN...WFO...BIS...LBF...UNR...BOU...CYS...BYZ...

   LAT...LON   40130499 44210505 45970504 46210410 45950324 44340278
               42980271 41080287 39730293 39180389 39500486 40130499 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN