Storm Prediction Center Mesoscale Discussion 1915

   Mesoscale Discussion 1915
   NWS Storm Prediction Center Norman OK
   0530 PM CDT Sat Aug 09 2025

   Areas affected...Northeast Colorado into adjacent portions of
   Nebraska and Kansas

   Concerning...Severe Thunderstorm Watch 581...

   Valid 092230Z - 100030Z

   The severe weather threat for Severe Thunderstorm Watch 581
   continues.

   SUMMARY...Upscale growth is anticipated in the next 2-3 hours across
   far northeast Colorado and adjacent portions of Nebraska and Kansas
   as storm interactions increase. This will be accompanied by an
   increase in severe wind potential.

   DISCUSSION...A mixture of left and right-split supercells continues
   across northeast CO with several reports of 1-2 inch hail and 50-60
   mph gusts noted over the past couple of hours. This convective
   evolution is indicative of a kinematic environment characterized by
   elongated, nearly-straight hodographs. With no appreciable change in
   the flow fields anticipated in the next several hours, this mix of
   splitting cells should continue for the near-term. One consequence
   of the mixed storm motions will be a tendency for increased storm
   interactions in the coming hours that should result in upscale
   growth and consolidation of cold pools as convection migrates east
   into higher buoyancy. Additionally, a subtle low-level confluence
   band noted in surface observations and KGLD reflectivity data may
   act as a foci for storm development/propagation. As such, the
   expectation is for gradual upscale growth over the next 2-3 hours
   across far northeast CO into northwest KS and southwest NE (though
   some uncertainty remains regarding the most likely corridor of
   downstream propagation). The potential for strong to severe winds
   should increase as this occurs. 

   Further south, a more isolated right-moving supercell near Limon, CO
   will likely maintain separation from the upscale growth to the
   north. Likewise, stronger capping and weaker forcing for ascent
   downstream should tend to limit additional development and help
   maintain storm isolated. Consequently, this cell will likely
   continue to pose a significant hail threat for the next couple of
   hours.

   ..Moore.. 08/09/2025

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

   ATTN...WFO...LBF...GLD...PUB...BOU...

   LAT...LON   39410406 39630384 40560296 40790282 40990247 41040212
               41050153 40930111 40790087 40470075 40090075 39790098
               39470128 39260169 39090218 38820305 38750349 38780381
               38970398 39150408 39410406 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN