Mesoscale Discussion 0260
NWS Storm Prediction Center Norman OK
0431 PM CDT Thu Mar 25 2021
Areas affected...northern GA...eastern TN...far western NC...extreme
upstate SC
Concerning...Severe potential...Watch possible
Valid 252131Z - 252330Z
Probability of Watch Issuance...60 percent
SUMMARY...A risk for severe thunderstorms, including the threat for
a couple of tornadoes, will likely develop over the next several
hours across northern GA and eastern TN. The risk will eventually
spread east into parts of the far western Carolinas later this
evening. The timing of an eventual watch issuance is a bit
uncertain.
DISCUSSION...Radar mosaic shows a broad rain shield across the
southern Appalachians as of 2130 UTC. A supercell over northwestern
GA, on the southern flank of the rain shield, will continue to move
east-northeast over northern GA the early evening hours. The
airmass across the southern Appalachians is currently
rain-cooled/stable but a strong moisture flux/destabilization will
likely occur during the evening hours. The richer low-level
moisture will likely reside across northern GA where lower 60s F
dewpoints are currently observed/expected this evening. In addition
to hail/wind risks with a supercell threat gradually spreading
northeastward into the area, a tornado or two is possible this
evening/tonight. For parts of southeast/eastern TN, the severe
threat will likely depend on storm development from the
west/southwest eventually moving into the region later this evening.
The expected timing of the risk will likely be delayed but begin in
a few hours.
