SPC AC 171241

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0741 AM CDT Sun Sep 17 2023

   Valid 171300Z - 181200Z

   ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTH ATLANTIC
   COASTAL PLAIN...

   ...SUMMARY...
   Isolated damaging winds and a tornado or two will be possible across
   portions of the south Atlantic coastal plain this afternoon into
   early tonight.

   ...South Atlantic coastal plain...
   Within a highly elongated upper trough from QC to the Lower MS
   Valley, primary shortwave impulses of interest will spread across
   parts of the TN Valley and southern Appalachians through the period.
   Minor deepening of a weak surface cyclone over central GA is
   expected as it tracks northeast to the Outer Banks of NC tonight. In
   the low-level warm advection regime ahead of this wave, a swath of
   showers is ongoing from the western Carolinas into east GA. This
   activity will likely persist through the day, mitigating the
   northward extent of surface-based destabilization within a poor
   mid-level lapse rate environment, especially over NC where surface
   dew points are generally in the upper 50s to low 60s. Isolated to
   scattered afternoon thunderstorms are more probable farther south
   over the SC/GA portion of the coastal plain after modest buoyancy
   ensues. Isolated gusts from 40-60 mph will be the main threat. 

   An increase in low-level SRH should occur this evening into early
   tonight, but likely be more pronounced along/north of the fringe of
   surface-based instability over land. A low probability threat for a
   brief tornado remains apparent, mainly across a portion of coastal
   SC to the Outer Banks, with greater potential for supercells
   producing waterspouts offshore.

   ..Grams/Gleason.. 09/17/2023

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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z