845
ACUS11 KWNS 231813
SWOMCD
SPC MCD 231813
NCZ000-VAZ000-TNZ000-KYZ000-SCZ000-GAZ000-231945-

Mesoscale Discussion 2097
NWS Storm Prediction Center Norman OK
0113 PM CDT Mon Sep 23 2024

Areas affected...Portions of southern Kentucky...middle/eastern
Tennessee and far western North Carolina

Concerning...Severe potential...Watch unlikely

Valid 231813Z - 231945Z

Probability of Watch Issuance...20 percent

SUMMARY...Convection should gradually expand in coverage this
afternoon with a few stronger multi-cell clusters possible. Isolated
damaging winds are the most likely threat with the more
persistent/stronger storms. Environmental conditions are not overly
conducive for longevity or severity, a watch appears unlikely.

DISCUSSION...As of 1810 UTC, afternoon visible and radar imagery
showed scattered thunderstorms developing south of a stationary
frontal zone over parts of the TN Valley and southern KY. Driven
primarily by strong diurnal heating of a seasonably moist (upper 60s
to low 70s F dewpoints) air mass, SPC mesoanalysis shows 1000-1500
J/kg of MLCAPE, despite poor mid-level lapse rates. In the absence
of significant height falls aloft, convective coverage should
gradually increase through the afternoon with continued heating.

As storms deepen, flow aloft will also gradually increase from the
west. While area VADs are not overly strong, especially with
eastward extent, 25-30 kt of flow aloft will support some potential
for organization into multi-cell clusters. Damaging winds associated
with water-loaded downdrafts appear to be the most likely threat
given poor low and mid-level lapse rates and limited storm
organization.

Hi-res model guidance and observational trends suggest storms will
gradually move eastward into parts of eastern TN/southeast KY and
the western Carolinas later this afternoon/evening. An isolated risk
for damaging winds will accompany the stronger/more persistent
clusters. However, the lack of more significant upper-level support,
poor lapse rates and marginal deep-layer shear suggests the threat
is unlikely to be widespread enough to warrant a WW.

..Lyons/Guyer.. 09/23/2024

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

ATTN...WFO...RNK...RLX...GSP...MRX...JKL...FFC...LMK...OHX...
HUN...

LAT...LON   37698535 36928641 36288662 35678647 35258610 35168512
            34918339 34948284 35218233 35468170 35818142 36348144
            37378254 37738517 37698535