Mesoscale Discussion 0925
   NWS Storm Prediction Center Norman OK
   0244 PM CDT Wed Jun 17 2020

   Areas affected...Portions of southern/eastern ND and northwestern MN

   Concerning...Severe potential...Watch possible 

   Valid 171944Z - 172145Z

   Probability of Watch Issuance...40 percent

   SUMMARY...At least an isolated large hail and severe wind gust
   threat may develop this afternoon. The need for a watch in the short
   term is uncertain. Still, watch issuance is possible in the next
   couple of hours.

   DISCUSSION...A band of elevated convection from earlier this morning
   has persisted into the early afternoon across parts of eastern ND.
   These storms are largely being aided by low-level warm advection. In
   the wake of this activity, the airmass along/east of a slow-moving
   front across central ND continues to destabilize this afternoon as
   surface temperatures warm into the upper 80s and low 90s. The
   presence of 7.0-7.5 C/km lapse rates in the 700-500 mb layer and mid
   to upper 60s surface dewpoints is also supporting MLCAPE of
   1500-2500 J/kg across the warm sector. Stronger mid-level
   southwesterly flow is lagging somewhat behind the surface front, but
   it should still be strong enough to support 30-40 kt of effective
   bulk shear and a mix of multicells and supercells.

   The primary uncertainty remains timing of surface-based convective
   initiation. Comparison of latest surface observations to recent RAP
   forecast soundings suggests that diurnal heating has been stronger
   than forecast, and convective inhibition is nearly eroded along and
   immediately east of the front in southern/eastern ND. If storms can
   form in the next couple of hours as subtle large-scale approaches
   from the southwest, they would likely strengthen and pose at least
   an isolated large hail and damaging wind threat given the favorable
   thermodynamic and kinematic environment. Given some
   veering/strengthening of the low-level wind field, a tornado cannot
   be ruled out, especially along/near the front while storms remain
   semi-discrete. The likelihood of storm initiation should increase
   after 22Z, but it may occur sooner. It remains unclear if watch
   issuance will be needed in the short term (next 1-2 hours), but
   observational trends will continue to be closely monitored.

   ..Gleason/Guyer.. 06/17/2020

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

   ATTN...WFO...FGF...BIS...

   LAT...LON   46020013 46780008 48459906 49079842 49049558 47869618
               45979799 46020013