Storm Prediction Center Mesoscale Discussion 983

   Mesoscale Discussion 0983
   NWS Storm Prediction Center Norman OK
   0731 PM CDT Thu Jun 04 2026

   Areas affected...Parts of SD and extreme northwest NE

   Concerning...Severe Thunderstorm Watch 272...273...

   Valid 050031Z - 050230Z

   The severe weather threat for Severe Thunderstorm Watch 272, 273
   continues.

   SUMMARY...The severe threat continues across parts of east-central
   South Dakota, with an increasing threat possible with time into
   south-central South Dakota.

   DISCUSSION...A cluster of intense storms has recently developed
   across east-central SD, to the west/north of Huron. This convection
   developed within a low-level confluence zone, within an environment
   characterized by MLCAPE of near/above 2000 J/kg and increasing
   effective shear in the 30-40 kt range. Large to locally very large
   hail and isolated severe gusts will continue to be a threat with
   these storms through mid evening, and a tornado cannot be ruled out
   given the presence of backed surface winds and modestly enhanced
   effective SRH. To the southwest of this cluster, isolated supercell
   development remains possible through dusk across south-central SD. 

   Later this evening, outflow associated with convection across
   western SD may begin to intersect richer moisture and stronger
   buoyancy along and north of a surface boundary. This could lead to
   upscale growth and development of a small MCS (as depicted by recent
   HRRR runs), though this evolution is uncertain due to a lack of
   stronger low-level flow. Should such an evolution occur, a greater
   threat for severe gusts could develop across southwest into central
   SD later this evening.

   ..Dean.. 06/05/2026

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

   ATTN...WFO...FSD...ABR...LBF...UNR...

   LAT...LON   44219675 43509816 42850071 42850153 42820252 43830286
               44290272 44510152 44580102 44879954 45019781 45049685
               44219675 

   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