Storm Prediction Center Mesoscale Discussion 1255

   Mesoscale Discussion 1255
   NWS Storm Prediction Center Norman OK
   0140 PM CDT Mon Jun 22 2026

   Areas affected...East-central to southeast Colorado

   Concerning...Severe potential...Watch likely 

   Valid 221840Z - 222045Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Thunderstorm development appears likely along the Front
   Range from central to southern Colorado in the next 1-2 hours. Watch
   issuance is likely as storms develop and spread east/southeast.

   DISCUSSION...Latest GOES imagery depicts growing cumulus from the
   Denver area southward along the Front Range and into the Raton Mesa
   within a weak upslope flow regime. This comes as temperatures begin
   to warm into the low to mid 80s, which latest CAM guidance suggests
   is required to erode mixed-layer inhibition and support convective
   initiation. Based on these satellite and temperature trends, deep
   convective initiation appears probable within the next 1-2 hours.

   Initially high-based convection will quickly spread east/southeast
   given the 30-40 knot west/northwest flow regime aloft. Steady
   intensification with eastward extent is expected as storms migrate
   into the axis of rich low-level moisture (dewpoints in the upper 50s
   to low 60s) in place along the eastern Plains. Additionally,
   elongated hodographs featuring 40-50 knots of effective bulk shear
   analyzed in recent mesoanalyses/forecast soundings (and confirmed by
   regional VWPs) will promote splitting supercells capable of large to
   very large hail (possibly as high as 2-3 inches) as well as strong
   outflow winds. Watch issuance will be needed this afternoon as
   initiation becomes more imminent and storms begin to mature.

   ..Moore/Hart.. 06/22/2026

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

   ATTN...WFO...DDC...GLD...AMA...PUB...BOU...ABQ...

   LAT...LON   36970280 37000336 37190395 37440450 37650481 37900503
               38230522 38670542 39010540 39270522 39400488 39420443
               39420397 39310341 39230321 38930273 38590235 38220211
               37820201 37390201 37190207 37070217 36970280 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN