Storm Prediction Center Mesoscale Discussion 1315

   Mesoscale Discussion 1315
   NWS Storm Prediction Center Norman OK
   0446 PM CDT Mon Jun 16 2025

   Areas affected...Parts of Nebraska into far western Iowa

   Concerning...Severe potential...Watch likely 

   Valid 162146Z - 162315Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Severe thunderstorms are expected to increase in both
   intensity and coverage over the next few hours. Large to very large
   hail and severe wind gusts will be the primary concerns. A watch is
   likely within the hour.

   DISCUSSION...A cluster of thunderstorms with a history of producing
   1-inch hail has been evolving along a cold front in far northeastern
   NE and far southeastern SD this afternoon, with additional
   development now ongoing southwestward along the front. Current
   indications are that additional thunderstorms will gradually evolve
   along/ahead of the surface front across NE over the next few hours,
   as continued diurnal heating of a moist air mass erodes antecedent
   inhibition at the base of the EML. Additional storms may also spread
   eastward into NE from southeast WY and northeast CO. The 20Z LBF
   sounding sampled steep deep-layer lapse rates and rich/deep
   boundary-layer moisture -- contributing to 3700 J/kg MLCAPE. This
   strongly unstable air, coupled with a long/straight hodograph
   (around 40 kt of effective shear), will favor supercell clusters
   capable of producing large to very large hail (some 2.5+ inch) and
   severe wind gusts. With time, strong outflow should promote upscale
   growth with an increasing severe risk for a swath of severe wind
   gusts. A watch will likely be issued within the hour for parts of
   the area.

   ..Weinman/Mosier.. 06/16/2025

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

   ATTN...WFO...FSD...OAX...GID...LBF...GLD...

   LAT...LON   41780172 42969765 42989671 42659609 41949583 41209609
               40919683 40569790 40070029 40060116 40440180 41300208
               41780172 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN