Mesoscale Discussion 2055
NWS Storm Prediction Center Norman OK
0225 PM CDT Sat Aug 26 2023
Areas affected…parts of the southern Appalachians into the central
Concerning…Severe potential…Watch unlikely
Valid 261925Z – 262130Z
Probability of Watch Issuance…5 percent
SUMMARY…Isolated strong to severe storms, with the potential for a
few damaging downburst gusts, will be possible this afternoon and
evening. A new WW is unlikely based on limited storm organization.
DISCUSSION…As of 1920 UTC, regional satellite imagery showed
deepening cumulus and incipient thunderstorms were maturing ahead of
a remnant MCV over portions of far eastern KY, southwestern VA and
eastern TN. Strong heating ahead of this feature, along with typical
diurnal terrain circulations should support additional thunderstorm
development through this afternoon. Moderate buoyancy (1000-2000
J/kg of MLCAPE) and fairly steep low-level lapse rates should
support occasional strong updrafts. Despite some flow enhancement
from the MCV, deep-layer is very weak, generally less than 20 kt.
This will favor multi-cellular, pulse storms with limited longevity.
As these storms mature, a few loosely organized clusters may
develop, but weak surface flow will also not favor strong cold pool
propagation. Thus, the severe threat should be limited to occasional
stronger downburst winds from downdraft pulses within individual
cell clusters or conglomerates. Given the lack of stronger
background forcing, the severe risk appears isolated and a weather
watch is unlikely.
…Please see www.spc.noaa.gov for graphic product…
LAT…LON 37238197 37338147 36768027 36087932 35307891 34677886
34267923 34017972 34058020 34068070 34068238 34348328
34558353 34768350 35178348 35648311 35888291 37238197