Storm Prediction Center Mesoscale Discussion 784

   Mesoscale Discussion 0784
   NWS Storm Prediction Center Norman OK
   0404 AM CDT Thu May 15 2025

   Areas affected...Parts of eastern SD into southwest MN and far
   northwest IA

   Concerning...Severe Thunderstorm Watch 250...

   Valid 150904Z - 151030Z

   The severe weather threat for Severe Thunderstorm Watch 250
   continues.

   SUMMARY...An isolated severe threat may spread northeast out of WW
   250 with time this morning.

   DISCUSSION...A long-lived storm cluster has evolved into a bowing
   MCS (with embedded cellular elements) from far eastern SD into
   southwest MN, and strong to locally severe gusts have been reported
   over the last hour to the northeast of Sioux Falls, SD. Small
   mesovortices have occasionally been noted along the leading edge of
   the line, and a threat for localized severe gusts could be maximized
   with these features, especially where the outflow has not surged
   ahead of the deeper convection. 

   The northern portion of the line will tend to move into a cooler and
   less unstable environment with time, though more substantial
   moisture return above the surface could maintain robust elevated
   convection through the early morning. The southern portion of the
   line will be in closer proximity to increasing MLCAPE and weaker
   MLCINH, though lingering near-surface stability may hamper
   reintensification potential.  

   An isolated severe threat may spread northeast out of WW 250 with
   time, though the need for downstream watch issuance is uncertain.

   ..Dean/Bunting.. 05/15/2025

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

   ATTN...WFO...MPX...DMX...FSD...ABR...

   LAT...LON   44179616 45139736 45729686 45619575 45459489 45319442
               45059420 44679403 44419403 43999424 43239470 42899540
               42889580 43099623 44179616 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN