Mesoscale Discussion 1723
   NWS Storm Prediction Center Norman OK
   0136 PM CDT Tue Sep 29 2020

   Areas affected...Portions of central/southern VA into NC/SC and
   eastern GA

   Concerning...Severe potential...Watch unlikely 

   Valid 291836Z - 292100Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Storms capable of producing isolated strong/gusty winds
   around 40-60 mph should continue through the afternoon. Watch
   issuance is unlikely.

   DISCUSSION...Thunderstorms are gradually strengthening this
   afternoon across parts of the western/central Carolinas along and
   just ahead of a surface cold front. Other isolated storms are
   ongoing across parts of coastal NC/SC. As a large-scale upper trough
   continues pivoting eastward across the OH/TN Valleys and Southeast,
   a weak surface low currently over western NC should develop
   northeastward into VA. The cold front trailing from this surface low
   will focus storm development through the remainder of the afternoon,
   with one or more broken lines of storms expected along its length
   from central VA to SC and eastern GA. 12Z observed soundings from
   RNK, GSO, MHX, and CHS all showed the presence of poor low and
   mid-level lapse rates. This should generally temper updraft
   strength, even as modest diurnal heating of a moist low-level
   airmass occurs. Still, around 500-1250 J/kg of MLCAPE has already
   developed ahead of the front per latest mesoanalysis estimates, with
   the slightly better instability farther south across eastern GA and
   vicinity.

   Various VWPs across this area show strong mid/upper level
   south-southwesterly winds that are nearly unidirectional. Around
   40-50 kt of effective bulk shear should foster some storm
   organization, with a mix of line segments and perhaps low-topped
   supercells possible. Isolated strong/gusty winds, generally in the
   40-60 mph range, may occur with any of these storms as they move
   slowly east-northeastward in tandem with the advancing cold front.
   With the poor lapse rates, weak instability, and strong flow aloft
   generally parallel to the surface front, the overall severe threat
   should remain isolated/marginal. Accordingly, watch issuance appears
   unlikely at this time.

   ..Gleason/Grams.. 09/29/2020

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

   ATTN...WFO...AKQ...MHX...LWX...RAH...ILM...RNK...CHS...CAE...
   GSP...JAX...FFC...

   LAT...LON   36567751 36347680 36077640 35537629 34807690 34517729
               34247771 33797796 33857848 33587891 33167911 32907948
               32078080 31128133 30758142 30968255 31338288 32098243
               32748209 33338185 34098153 34708139 35518117 36688062
               38237861 38177782 36567751