Mesoscale Discussion 1571
   NWS Storm Prediction Center Norman OK
   0218 PM CDT Tue Aug 25 2020

   Areas affected...Parts of far eastern Oregon...central Idaho...and
   southwest Montana

   Concerning...Severe potential...Watch unlikely 

   Valid 251918Z - 252115Z

   Probability of Watch Issuance...5 percent

   SUMMARY...A couple damaging gusts are the most likely severe threat
   with the stronger storm cores. A couple marginally severe hailstones
   also cannot be completely ruled out. A WW issuance is not
   anticipated.

   DISCUSSION...Diurnal heating of the boundary layer is expected to
   continue through the afternoon hours, with deep mixing expected.
   Surface temperatures in the 70s to near 80F and near 50F dewpoints,
   along with 8+ C/km 0-3km lapse rates, are contributing to 250-500
   J/kg MLCAPE, adequate to support relatively vigorous convection. The
   latest RAP forecast soundings depict classic inverted-v soundings
   extending up to 600-500 mb, suggesting that efficient downward
   momentum transport via evaporative cooling may support damaging
   gusts with the stronger, longer lasting storms. Given steep
   tropospheric lapse rates, occasional large hail may also accompany
   the deepest storm cores (albeit marginally severe at best given
   limited buoyancy and expected melting through a deep, dry sub-cloud
   layer). 

   The isolated nature of the severe threat precludes a WW issuance.

   ..Squitieri/Bunting.. 08/25/2020

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

   ATTN...WFO...BYZ...TFX...SLC...PIH...MSO...BOI...LKN...

   LAT...LON   41481819 43251672 44861470 45861274 46041161 45221103
               44261138 43121283 42161390 41561424 41241461 41061689
               41481819