Storm Prediction Center Mesoscale Discussion 1809

   Mesoscale Discussion 1809
   NWS Storm Prediction Center Norman OK
   0456 PM CDT Sat Aug 03 2024

   Areas affected...eastern South Dakota into central/southern
   Minnesota

   Concerning...Severe potential...Watch possible 

   Valid 032156Z - 040000Z

   Probability of Watch Issuance...60 percent

   SUMMARY...Severe thunderstorm potential is increasing late this
   afternoon across eastern South Dakota into central/southern
   Minnesota. Timing for thunderstorm development is uncertain, but
   this area is being monitored for possible watch issuance.

   DISCUSSION...A surface low is located over north-central MN this
   afternoon, with a trailing cold front dropping south across
   northeast South Dakota/far southeast North Dakota and west-central
   MN. A warm front extends south/southeast from the low over eastern
   MN. Between these surface boundaries, a very moist airmass is in
   place with dewpoints in the upper 60s to low 70s F. Heating into the
   mid 80s to low 90s F has weakened MLCIN, especially across western
   portions of the discussion area. Steep midlevel lapse rates near 8
   C/km atop the moist boundary layer are contributing to a corridor of
   strong instability ahead of the south/southeastward progressing cold
   front. Visible satellite imagery shows deepening cumulus near the
   front, with some modest development within the broader warm sector. 

   Vertically veering wind profiles, with effective shear magnitudes
   greater than 35 kt will support organized convection. Initial
   supercells capable of large to very large hail are possible. With
   time, convection may cluster into a southeastward progressing MCS
   later this evening, posing a increasing risk for damaging gusts.
   Timing of thunderstorm development remains uncertain, but given
   satellite trends, expected storms to develop within the next couple
   of hours. Furthermore, at least weak MLCIN will likely persist with
   eastward extent. This may confine overall severe potential to a
   relatively narrow corridor. This area will continue to be monitored
   for possible watch issuance in the next couple of hours.

   ..Leitman/Smith.. 08/03/2024

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

   ATTN...WFO...DLH...MPX...FGF...FSD...ABR...

   LAT...LON   46619510 46599635 46339674 46139759 45409821 44919831
               44229800 43709728 43599682 43619607 43629462 43759366
               44349339 45339334 45879351 46269396 46619510