MD 0176 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR TN VALLEY TO SOUTHERN APPALACHIANS
Mesoscale Discussion 0176
NWS Storm Prediction Center Norman OK
0856 AM CST Wed Feb 28 2024
Areas affected…TN Valley to southern Appalachians
Concerning…Severe potential…Watch unlikely
Valid 281456Z – 281700Z
Probability of Watch Issuance…20 percent
SUMMARY…Southern portion of a low-topped squall line should
continue eastward across parts of the Tennessee Valley through at
least midday. Strong to localized severe wind gusts capable of
sporadic damage should be the primary threat.
DISCUSSION…The southern portion of a long, but thin, low-topped
(echo tops to around 30k ft) squall line extends as far south as
northeast MS. Large-scale ascent, outside of low-level convergence
attendant to the southeast-moving cold front, will be gradually
weakening across the region into the afternoon. However, a few cloud
breaks noted ahead of the line should yield modest boundary-layer
destabilization. In conjunction with the northeast extent of low 60s
surface dew points, the relatively more favorable thermodynamic
environment should compensate for the diminishing ascent and will
probably sustain the low-topped convective line eastward through at
least midday. This scenario is generally supported by 12Z CAM
guidance. With veered surface and low-level flow, increasing to
40-45 kts at 1 km AGL, the primary threat should be strong to
locally severe surface gusts, peaking in the 50-65 mph range. A
53-kt gust was measured at KMSL at 1437Z.
..Grams/Guyer.. 02/28/2024
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…GSP…MRX…FFC…OHX…BMX…HUN…MEG…JAN…
LAT…LON 35578600 35818470 35458401 35098380 34608371 34258386
33948462 33558572 33448683 33518828 33618872 34638751
35578600