Storm Prediction Center Mesoscale Discussion 1357

   Mesoscale Discussion 1357
   NWS Storm Prediction Center Norman OK
   0618 PM CDT Sat Jun 27 2026

   Areas affected...portions of western Kentucky

   Concerning...Severe Thunderstorm Watch 403...

   Valid 272318Z - 280015Z

   The severe weather threat for Severe Thunderstorm Watch 403
   continues.

   SUMMARY...A corridor of locally greater severe potential may exist
   across portions of Severe Thunderstorm Watch 403 along remnant
   outflow boundary.

   DISCUSSION...Latest surface analysis places a remnant outflow
   boundary from just south of Paducah, Kentucky, into northern
   Tennessee. Convection along this boundary in the vicinity of PAH has
   exhibited marginal supercell structures with weak rotation
   signatures over the past 1-2 hours. A moist and unstable air mass
   south of the remnant boundary aided by 40-50 kts of mid-level flow
   (sampled by regional VWPs) and effective shear of around 30 kts
   along the southern flank of two mid-level MCVs will continue to
   support marginal supercell structures through this evening, with the
   latest high-res guidance suggesting that this convection may
   continue to progress along this boundary. In this scenario, a
   corridor of locally greater severe potential may develop, with the
   potential for water-loaded downbursts and damaging wind gusts. A
   brief tornado or two is also possible given enhanced low-level shear
   along this boundary (~100 m2/s2 0-500 m SRH sampled downstream of
   the aforementioned convection by the HPX/OHX VWPs).

   ..Chalmers.. 06/27/2026

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

   ATTN...WFO...LMK...OHX...PAH...

   LAT...LON   37338864 37338839 37268771 37178725 37018696 36828683
               36658693 36628717 36678766 36828834 36978866 37118878
               37338864 

   MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH