Storm Prediction Center Mesoscale Discussion 656

   Mesoscale Discussion 0656
   NWS Storm Prediction Center Norman OK
   0351 PM CDT Mon May 06 2024

   Areas affected...South-central to northwest South Dakota

   Concerning...Severe Thunderstorm Watch 188...

   Valid 062051Z - 062245Z

   The severe weather threat for Severe Thunderstorm Watch 188
   continues.

   SUMMARY...The potential for severe hail/wind continues across
   portions of south-central to northwest South Dakota, especially in
   the near-term (next 1-2 hours). This threat is expected to gradually
   diminish heading into the evening hours.

   DISCUSSION...Regional radar imagery and MRMS data over the past hour
   continue to show a broken line of strong to severe cells along an
   arching cold front from northwest to south-central SD. While many of
   these cells have been relatively short-lived after they move off the
   initiating boundary, new updraft development is noted within an
   environment that remains favorable for organized convection (SBCAPE
   between 1000-2000 J/kg with 35-40 knot effective bulk shear). The
   expectation for the near-term is for ongoing cells and developing
   storms to show periodic intensification to severe limits with an
   associated risk of large hail and severe wind gusts. Latest
   mesoanalysis suggests ample low-level vorticity continues to reside
   along the front with sufficient low-level buoyancy for vertical
   stretching (especially where temperatures have warmed into the upper
   60s/low 70s) that may support a low-end tornado threat. 

   Beyond the next 2 hours, the surface low over western SD is expected
   to gradually begin occluding with the cessation of northerly
   transport of higher theta-e air, effectively isolating the effective
   warm front. Early signs of this are already noted with the
   development of a line of storms across south-central SD along a more
   meridional section of the cold front. With the loss of buoyant
   low-level moisture return, convective intensity should gradually
   diminish.

   ..Moore.. 05/06/2024

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

   ATTN...WFO...ABR...BIS...LBF...UNR...BYZ...

   LAT...LON   44770011 44229993 43649981 43219985 42969997 42840018
               42760039 42890067 43480100 43960122 44350165 44630217
               44880275 45100336 45060388 45040417 45270446 45610453
               45780446 46040418 46210354 46260298 46260248 46100161
               45890116 45430062 44770011