Mesoscale Discussion 0326
NWS Storm Prediction Center Norman OK
0312 PM CDT Wed Mar 23 2022
Areas affected...Parts of the South Carolina into North Carolina
Piedmont
Concerning...Severe potential...Watch possible
Valid 232012Z - 232245Z
Probability of Watch Issuance...40 percent
SUMMARY...Scattered strong thunderstorm development, including one
or two supercells posing a risk for tornadoes, appears possible by
6-8 PM EDT. While it is not certain that a severe weather watch
will be needed, trends are being monitored for this possibility.
DISCUSSION...Low-level warm air and moisture advection, and
insolation with increasing breaks in cloud cover, are contributing
to gradual boundary-layer destabilization along a remnant surface
frontal zone across the Piedmont. With further insolation, and weak
cooling in the 700-500 layer forecast through late afternoon, models
suggest that mixed-layer CAPE on the order of 500-1000 J/kg may
develop. It appears that this will coincide with the
east-northeastward propagation of a 45-50 kt speed maximum around
850 mb.
Mid/upper forcing for ascent appears likely to remain generally
weak, but models have been suggestive that scattered discrete
thunderstorm development is increasingly possible through 22-00Z.
With deep-layer shear already strong, beneath 50-70 kt southwesterly
flow around 500 mb, enlarging, clockwise-curved low-level hodographs
may become favorable for the evolution of at least one or two
supercells that may pose a risk of producing tornadoes.