Mesoscale Discussion 1026
   NWS Storm Prediction Center Norman OK
   0218 PM CDT Sat Jun 08 2019

   Areas affected...Portions of northeast Colorado...far northwest
   Kansas...southwest into central Nebraska

   Concerning...Severe potential...Watch likely 

   Valid 081918Z - 082045Z

   Probability of Watch Issuance...80 percent

   SUMMARY...An increase in convective coverage is expected over the
   next few hours, with storms initiating mainly along the cold front,
   and perhaps along a weak confluence zone. The more organized storms
   may pose a damaging wind/large hail threat, with isolated very large
   hail possible, especially across parts of northeast Colorado into
   southwest Nebraska. A WW issuance will likely be needed by 20Z to
   address the severe potential.

   DISCUSSION...A cold front continues to sag southward across the
   area, where multiple hours of insolation, beneath relatively steep
   (7.0+ C/km) lapse rates throughout the troposphere, has contributed
   to weakening convective inhibition and increasing instability (with
   up to 2000 J/kg MLCAPE noted). At least one low-level confluence
   zone was identified via visible satellite imagery, which may
   contribute to low-level lift for additional convection to initiate
   later this afternoon. Compared to areas farther north, mid-level
   flow will be oriented somewhat more perpendicular to the cold front,
   suggesting that convection may be more quasi-discrete in nature,
   with both multicellular clusters supercells possible. A couple
   sustained supercell structures, perhaps producing isolated instances
   of very large hail, may be observed in northeast Colorado into
   southwest Nebraska, where sfc-500 mb lapse rates of 7.5-8.0 C/km are
   expected. 

   Current thinking is that convection will first initiate immediately
   along the cold front across central Nebraska into northeast Colorado
   in the next couple of hours. A WW issuance will likely be needed by
   20Z to address both developing severe threats.

   ..Squitieri/Thompson.. 06/08/2019

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

   ATTN...WFO...FSD...OAX...GID...LBF...UNR...GLD...BOU...

   LAT...LON   39920439 41320195 42850049 43389916 42989800 41289789
               40619815 39769990 38870333 39920439