Mesoscale Discussion 1061
   NWS Storm Prediction Center Norman OK
   0525 PM CDT Tue Jun 30 2020

   Areas affected...Southeast North Dakota and eastern South Dakota

   Concerning...Severe potential...Watch likely 

   Valid 302225Z - 010030Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Numerous storms are expected along and ahead of a cold
   front this evening. The primary threats will be large hail and
   damaging winds.

   DISCUSSION...22Z surface analysis shows a strong cold front from
   southern North Dakota into central and east central South Dakota.
   The environment ahead of this front is very moist and unstable with
   dewpoints in the mid 70s and temperature in the upper 80s to near
   90. This has yielded MLCAPE in excess of 5000 J/kg with CINH
   recently eroded. Most of the upper-level forcing is farther west and
   thus, storm development will likely be confined to low-level
   boundaries. This includes the cold front which is surging eastward
   across southern North Dakota and central South Dakota and a
   confluence zone east of Aberdeen. Despite very strong instability,
   storms may struggle to organize (similar to the storms in Brown
   County, SD between 22Z and 2220Z) due to the warm nose around 700mb
   (per RAP soundings) and relatively weak flow above 1-2 km (per ABR
   VWP). In addition, storm motions may take some updrafts to the cool
   side of the cold front rather quickly which may also limit the
   duration of any severe threat. However, despite these negative
   factors, storms are expected to be numerous along the front and
   mid-level lapse rates are very steep (~8.5 C/km per SPC
   mesoanalysis). Therefore, even if storms remain somewhat loosely
   organized, there will be a threat for large hail and damaging winds
   with the stronger updrafts which are able to realize faster
   mid-level parcel accelerations associated with the steep lapse
   rates.

   ..Bentley/Guyer.. 06/30/2020

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

   ATTN...WFO...FGF...FSD...ABR...BIS...

   LAT...LON   43889895 44829935 45870000 46520056 46800092 47010124
               47080091 47069974 47029859 46989730 46929710 46369692
               45079672 44109712 43759802 43699848 43549887 43889895