Mesoscale Discussion 1833
   NWS Storm Prediction Center Norman OK
   1121 PM CST Fri Dec 04 2020

   Areas affected...Outer and Inner Banks vicinity of North Carolina

   Concerning...Severe potential...Watch unlikely 

   Valid 050521Z - 050715Z

   Probability of Watch Issuance...20 percent

   SUMMARY...A couple of supercells may develop across the region
   through 1-2 AM EST, accompanied by the potential to produce a
   tornado or locally strong surface gusts.  While it is not clear that
   a severe weather watch will be needed, trends are being monitored.

   DISCUSSION...Steady deepening of the surface cyclone is ongoing and
   likely to continue into the overnight hours, as the supporting
   vigorous mid-level short wave impulse pivots east-northeast of the
   Great Smoky Mountains vicinity toward the southern Mid Atlantic
   coast.  The cyclone center will continue to migrate northeast of
   Raleigh NC, toward the Hampton Roads vicinity through 07-09Z, with a
   trailing cold front surging into North Carolina coastal areas.

   A combination of generally weak lapse rates and limited moisture
   return off the western Atlantic has suppressed convective
   development to this point.  Lightning has been sparse, and most
   recent lightning flashes have been with post-frontal convection
   beneath the mid-level cold core.

   However, based on recent objective analysis, boundary-layer
   moistening across the waters off the south Atlantic Seaboard is
   finally becoming sufficient to support appreciable CAPE.  Latest NAM
   and Rapid Refresh forecast soundings suggest that some of this
   moisture could advect into the Outer and Inner Banks vicinity of
   North Carolina by 06-07z.  It appears that this may coincide with
   enlarging clockwise curved low-level hodographs, beneath southerly
   850 mb flow strengthening in excess of 50 kt.

   Discrete convective development appears underway within the narrow
   corridor of low-level moistening and destabilization, in the wake of
   a cluster of warm advection supported convection spreading
   northeastward offshore.  Some of these cells may continue to
   intensify during the next couple of hours, taking on supercell
   structure and posing the risk for a tornado, in addition to locally
   strong surface gusts.

   ..Kerr/Thompson.. 12/05/2020

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

   ATTN...WFO...MHX...

   LAT...LON   36017582 35987504 34797555 34667679 35427633 36017582