Storm Prediction Center Mesoscale Discussion 2158

   Mesoscale Discussion 2158
   NWS Storm Prediction Center Norman OK
   0323 PM CDT Thu Oct 24 2024

   Areas affected...parts of northeast Kansas...southeast
   Nebraska...northwest Missouri...southwest Iowa

   Concerning...Severe potential...Watch unlikely 

   Valid 242023Z - 242300Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Widely scattered strong thunderstorm development posing a
   risk for severe hail and potentially damaging wind gusts are
   possible by 5-7 PM CDT.  This may include an isolated evolving
   supercell near/east of the I-29 corridor between Kansas City and St.
   Joseph.

   DISCUSSION...Rapid surface pressure falls (2 hourly on the order of
   4 mb) have been evident in the 19-20Z observations centered around
   Topeka.  This is within broader surface troughing encompassing much
   of the central Great Plains, where models indicate modest surface
   wave development along a strengthening low-level baroclinic zone. 
   It appears that low-level moistening and destabilization will become
   focused within strengthening large-scale ascent associated with
   downstream low-level warm advection, across northeast Kansas into
   northwest Missouri through 22-00Z.  This likely will be aided by the
   approach of a mid-level short wave trough now turning east of the
   Wyoming/Colorado Rockies.

   To the east of a plume of relatively warm elevated mixed-layer air
   overspreading the central Great Plains, it appears that a narrow
   tongue of modest low-level moisture return (including upper 50s/near
   60F surface dew points) will contribute to CAPE as high as 1000+
   J/kg.  As the large-scale ascent overcomes the mid-level inhibition,
   the initiation of at least a couple of strong thunderstorms appears
   increasingly probable by early evening, in the presence of favorably
   sheared, 30-40 kt southwesterly to westerly flow in the 850-500 mb
   layer.

   The environment appears conducive to a risk for severe hail. 
   Additionally, modestly steep lower/mid-tropospheric lapse rates and
   sizable sub-cloud temperature/dew point spreads may support a risk
   for potentially damaging wind gusts, even for increasingly elevated
   storms to the east of the surface warm front forecast to shift into
   the Kansas City/St. Joseph MO vicinity by early evening.  It appears
   that the most favorable shear and instability will focus in close
   proximity to the front, providing support for the highest
   probabilities for sustained supercell development.  However, even
   with sizable, clockwise curved low-level hodographs, the relatively
   dry/well-mixed boundary-layer probably will tend to limit the
   tornado potential.

   ..Kerr/Gleason.. 10/24/2024

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

   ATTN...WFO...DMX...EAX...OAX...TOP...

   LAT...LON   39259626 40029580 40779407 40099247 39609300 39259439
               38909550 38859594 39259626