Storm Prediction Center Mesoscale Discussion 2136

   Mesoscale Discussion 2136
   NWS Storm Prediction Center Norman OK
   0355 PM CDT Sat Oct 04 2025

   Areas affected...northeast Colorado...southeast Wyoming...and the
   Nebraska Panhandle

   Concerning...Severe potential...Watch possible 

   Valid 042055Z - 042300Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Thunderstorms will increase in coverage and intensity this
   afternoon. Isolated severe hail and wind may occur with the
   strongest cores. A watch is not anticipated in the short term, but
   trends will be monitored.

   DISCUSSION...Thunderstorms are developing this afternoon along and
   north of a remnant surface boundary stretched along the
   Colorado-Wyoming border. These storms appear to be related to weak
   warm-air advection between 850 and 700 millibars. This activity is
   developing within a weakly unstable atmosphere, with most-unstable
   CAPE between 500 and 1000 J/kg, although low-level moisture and
   mid-level lapse rates remain rather poor. 

   Additional thunderstorms will be possible later this afternoon into
   the evening as an approaching cold front moves east toward the
   region. The cold front should  provide a more focused area for
   convective development, and the strongly forced ascent along the
   front may support more robust updrafts than currently observed.
   These thunderstorms may tap into the strong flow aloft as the core
   of mid-level jet streak moves over the region. 

   The combination of cool temperatures aloft and stronger flow aloft
   may support an isolated severe hail or wind gust this evening. A
   watch is currently not anticipated in the short term, but conditions
   will continue to be monitored and one may be necessary later this
   afternoon.

   ..Marsh/Gleason.. 10/04/2025

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

   ATTN...WFO...LBF...BOU...CYS...

   LAT...LON   41000498 41710488 42180450 42430367 42370298 42100249
               41690238 40650270 40290345 40200427 40370472 41000498 

   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN