Storm Prediction Center Mesoscale Discussion 940

   Mesoscale Discussion 0940
   NWS Storm Prediction Center Norman OK
   0438 PM CDT Mon Jun 01 2026

   Areas affected...portions of southeast Wyoming into eastern Colorado
   and western Nebraska

   Concerning...Severe Thunderstorm Watch 262...

   Valid 012138Z - 012245Z

   The severe weather threat for Severe Thunderstorm Watch 262
   continues.

   SUMMARY...Supercells will continue across southeastern Wyoming into
   eastern Colorado over the next few hours, accompanied by a severe
   hail threat. A tornado is also possible.

   DISCUSSION...Multiple supercells, with a history of severe hail and
   occasional low-level rotation (especially over CO east of Denver),
   persist amid appreciable low-level upslope flow and 40 kts of
   effective bulk shear, but marginal instability (i.e. 1000 J/kg
   MLCAPE). Given 8+ C/km mid-level lapse rates preceding the ongoing
   storms, severe hail should continue over the next several hours.
   KFTG and TDEN storm relative velocity data have shown low-level
   rotation with storms east of Denver to be relatively brief.
   Nonetheless, ample low-level vertical oriented vorticity exists near
   these storms, so a landspout/hybrid tornado cannot be ruled out if
   an updraft can ingest this vorticity for an appreciable amount of
   time before being undercut by outflow.

   ..Squitieri.. 06/01/2026

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

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

   LAT...LON   39060458 40120498 40670512 41630482 42110446 42670382
               42770315 42440248 41440219 40180216 39530222 39070244
               38920292 38890371 39060458 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN