ACUS11 KWNS 211931

SWOMCD

SPC MCD 211931 

SCZ000-NCZ000-TNZ000-VAZ000-KYZ000-GAZ000-212130-



Mesoscale Discussion 0283

NWS Storm Prediction Center Norman OK

0231 PM CDT Sat Mar 21 2026



Areas affected...the Southern Appalachians into the Carolinas



Concerning...Severe potential...Watch unlikely 



Valid 211931Z - 212130Z



Probability of Watch Issuance...5 percent



SUMMARY...Isolated to widely scattered thunderstorms may pose a

threat for occasional damaging wind gusts and marginally severe hail

this afternoon/evening. Watch issuance is unlikely.



DISCUSSION...Latest regional surface analysis depicts surface

dewpoints in the upper-40s to low-50s F amid deep, well-mixed

boundary layer profiles. Despite this limited low-level moisture,

cool temperatures and steep lapse rates in the mid-levels are

helping to support weak buoyancy, with latest mesoanalysis

indicating the presence of 500-750 J/kg MLCAPE across portions of

Middle and eastern Tennessee. As modest ascent increases ahead of an

approaching mid-level trough and convective temperatures are reached

over the next few hours, isolated to widely scattered thunderstorm

development is expected across the southern Cumberland and Blue

Ridge Mountains. While mid/upper level flow will remain weak to

modest (effective bulk shear of only 25-30 kts), some limited storm

organization is possible. Marginally severe hail may accompany the

strongest cores amid an initially cellular storm mode. With time, a

gradual evolution toward a more linear/line segment mode is then

expected as storms move east-southeastward. Steep low-level lapse

rates (8.5+ C/km) and DCAPE of 600-900 J/kg (locally higher) will

support the potential for isolated strong to damaging wind gusts.

The onset of nocturnal boundary-layer stabilization should then

result in a decreasing severe threat later this evening as the

storms move into the coastal Carolinas.



..Chalmers/Leitman.. 03/21/2026



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



ATTN...WFO...RNK...CAE...GSP...MRX...JKL...FFC...



LAT...LON   35508468 35828467 36248453 36568421 36708366 36668308

            36168178 35828091 35608060 35278052 34838053 34418075

            34138143 34408249 34988395 35198450 35508468 



MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH

MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN