Mesoscale Discussion 0945
   NWS Storm Prediction Center Norman OK
   1132 AM CDT Sun Jun 13 2021

   Areas affected...central Maryland into northern Virginia

   Concerning...Severe potential...Watch unlikely 

   Valid 131632Z - 131830Z

   Probability of Watch Issuance...20 percent

   SUMMARY...A few damaging gusts may accompany the leading line of
   storms. A WW issuance is not currently expected given the sparse
   nature of the severe threat.

   DISCUSSION...KLWX and MRMS mosaic radar imagery have shown a recent
   uptick in intensity along the leading line of an MCS that has been
   in progress for the past few hours. This line has likely been
   elevated, however, the associated cold pool is now propagating into
   a 75-80 F surface airmass, where the boundary-layer should have
   mixed to some degree (based on modified RAP forecast soundings). A
   transition to a more surface-based MCS is likely over the next
   couple of hours, where wet downbursts may support a few damaging
   gusts. However, troposheric winds and deep-layer ascent are both
   quite weak, and buoyancy is expected to be limited (generally below
   500 J/kg MLCAPE) given poor low/mid-level lapse rates and mid to
   upper 60s F dewpoints. As such, damaging gusts are expected to
   remain isolated and a WW issuance is not currently anticipated.

   ..Squitieri/Grams.. 06/13/2021

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

   ATTN...WFO...AKQ...LWX...

   LAT...LON   39077855 39497816 39657778 39657721 39477672 38977645
               38537641 38227663 38127706 38197757 38587818 39077855