Mesoscale Discussion 1627
   NWS Storm Prediction Center Norman OK
   1108 AM CDT Sat Aug 29 2020

   Areas affected...Portions of southern NJ...DE...central/eastern
   MD...DC...eastern VA...and eastern NC

   Concerning...Severe potential...Watch possible 

   Valid 291608Z - 291845Z

   Probability of Watch Issuance...40 percent

   SUMMARY...A threat for damaging winds and perhaps a tornado or two
   may increase this afternoon. Watch issuance is possible for portions
   of the area.

   DISCUSSION...A mid-level shortwave trough (remnants of Laura)
   evident on water vapor satellite imagery is located over VA and the
   Carolinas at 16Z. Large-scale ascent associated with this feature
   may encourage isolated to perhaps scattered thunderstorms by early
   this afternoon from southern NJ to eastern NC, even though low-level
   convergence will likely remain weak. Modest diurnal heating of a
   very moist low-level airmass has already occurred this morning
   across this region, with MLCAPE generally in the 1000-2000 J/kg
   range (stronger with southward extent). 30-40 kt of low/mid-level
   southwesterly flow will support fast east-northeastward storm
   motions, There should also be enough, albeit marginal (25-35 kt),
   effective bulk shear sufficient for some storm organization.

   There is still uncertainty regarding overall storm coverage given
   the lack of stronger low-level convergence. Storm intensity is also
   in question, as very poor mid-level lapse rates may tend to limit
   updraft accelerations. Still, any storms that do form may be capable
   of clustering and producing damaging winds given the enhanced
   low/mid-level flow. A tornado or two also appears possible, but
   limited veering of winds in the surface to 850 mb layer suggests
   only modest effective SRH (100-150 m2/s2) will be present.
   Convective trends will be closely monitored for possible watch
   issuance across some part of this region through the afternoon.

   ..Gleason/Grams.. 08/29/2020

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

   ATTN...WFO...PHI...AKQ...MHX...LWX...RAH...ILM...

   LAT...LON   34537656 34437748 34657838 37007793 39427713 39687574
               39707508 39507423 38917481 38357501 37857532 36917597
               36137569 35637542 35217550 34537656