Mesoscale Discussion 1367
   NWS Storm Prediction Center Norman OK
   0336 PM CDT Thu Jul 04 2019

   Areas affected...northern Nebraska and southern South Dakota

   Concerning...Severe potential...Watch possible 

   Valid 042036Z - 042230Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Convection is increasing near/east of Chadron, though
   convective trends over the next 2-3 hours are uncertain.

   DISCUSSION...Recent convection has intensified about 10-40 miles
   east of CDR over the past half hour.  This is likely due to
   sustained surface convergence along a weak remnant frontal boundary
   and minimal inhibition above that convergence.  These storms are in
   a weakly to moderately unstable environment (around 2500 J/kg
   MUCAPE), with a weak easterly component to surface flow beneath
   25-30 kt mid-level flow contributing to shear profiles marginally
   favorable for organization and even updraft rotation.  The lack of
   any forcing aloft lends some doubt to any continued expansion of
   convection in the discussion area, with any surface-based
   development likely tied to convergence along the front.  Any storm
   that can root near the boundary and ingest attendant vorticity may
   obtain brief updraft rotation and pose a very isolated tornado risk.
    Otherwise, large hail and damaging wind gusts will be the greatest
   risk with this activity, although the bulk of the severe threat may
   hold off until much later in the evening.

   ..Cook/Grams.. 07/04/2019

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

   ATTN...WFO...FSD...LBF...UNR...CYS...

   LAT...LON   43050317 43190215 43300057 43209960 42549896 42049895
               41509993 41690169 42100290 42590328 42770325 43050317