Storm Prediction Center Mesoscale Discussion 778

   Mesoscale Discussion 0778
   NWS Storm Prediction Center Norman OK
   0307 PM CDT Wed May 14 2025

   Areas affected...Southwest into central Nebraska

   Concerning...Severe potential...Watch likely 

   Valid 142007Z - 142200Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Large/very-large hail and severe winds will be the primary
   threats as storms develop and mature this afternoon and evening.
   Supercells on the southern end of the activity may have slightly
   higher associated tornado threat. A watch is likely late this
   afternoon.

   DISCUSSION...Dewpoints have held in the low 60s F in central
   Nebraska this afternoon. Cumulus towers and recent lightning have
   been observed in Cherry County in the last hour along a surface
   boundary. Water vapor imagery shows ascent increasing in Colorado as
   a shortwave trough continues to pivot northeastward. This ascent
   should reach western/southwestern Nebraska later this afternoon. In
   the near term, additional storms appear probable as
   heating/convergence continue along the boundary. The eastern
   boundary is the most likely zone for initiation, though additional
   storms could form on the weaker boundary to the west. With
   deep-layer shear having a more westerly component this far south,
   which should be maintained/modestly increase as the trough ejects
   this evening, a mixed mode of linear segments and supercells can be
   expected. Supercells will be favored with southern extent.

   Modestly steep mid-level lapse rates and increasing shear by the
   evening will support organized storms capable of large/very-large
   hail (particularly supercells) and severe winds. While the low-level
   jet response this evening is not expected to be overly strong, a
   supercell along the southern flank of the activity may have slightly
   higher tornado potential.

   A watch is likely by late afternoon. Timing of watch issuance is
   somewhat uncertain given greater storm coverage may wait until
   greater mid-level ascent arrives by 22-00Z.

   ..Wendt/Gleason.. 05/14/2025

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

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

   LAT...LON   40060159 40500190 40890205 41400216 41980178 42400146
               42820115 42990093 42800012 42179978 41089959 40599978
               40180025 40010067 40060159 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN