Alert archive / Tennessee / Mesoscale Discussions in 2021
Mesoscale Discussion 141
The Storm Prediction Center issued this mesoscale discussion at Feb 28, 2021, 7:16 PM CST for 6 counties in Kentucky; 22 counties in Tennessee. It was in force for 59 min.
The area
The outline as issued.
The facts
- Issued
- Feb 28, 2021, 7:16 PM CST (01:16 UTC)
- Expired
- Feb 28, 2021, 8:15 PM CST
- In force
- 59 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 15
All 28 counties
Allen County, KY, Clinton County, KY, Cumberland County, KY, Metcalfe County, KY, Monroe County, KY, Wayne County, KY, Bedford County, TN, Bledsoe County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Grundy County, TN, Jackson County, TN, Macon County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Rutherford County, TN, Smith County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Wilson County, TN
The radar
The Nashville radar (KOHX), 90 km from the middle of the area, began a volume at 01:17 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 00:00Z, 1.3 hours before the alert went out and 95 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 419 J/kg
- Mixed-layer CIN
- -8 J/kg
- Mixed-layer LCL
- 979 m above ground
- 0-6 km bulk shear
- 66 kt
- 0-1 km storm-relative helicity
- 220 m²/s²
- 0-3 km storm-relative helicity
- 278 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 4.5
The text
As transmitted.
080
ACUS11 KWNS 010116
SWOMCD
SPC MCD 010116
KYZ000-TNZ000-010215-
Mesoscale Discussion 0141
NWS Storm Prediction Center Norman OK
0716 PM CST Sun Feb 28 2021
Areas affected...0Portions of eastern Tennessee and southern
Kentucky
Concerning...Severe Thunderstorm Watch 15...
Valid 010116Z - 010215Z
The severe weather threat for Severe Thunderstorm Watch 15
continues.
SUMMARY...A severe thunderstorm watch has been issued for portions
of eastern Tennessee and southern Kentucky.
DISCUSSION...Ongoing convection is expected to maintain some severe
potential as it continues east given the moist downstream
environment. Slightly cooler temperatures have yielded lower
instability across this region in the 250 to 500 J/kg range.
However, this will still be sufficient for some damaging wind
potential and a brief tornado or two, especially given the very
strong wind field with 50 to 55 kts of flow at 1km per OHX VWP.
..Bentley/Grams.. 03/01/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MRX...JKL...LMK...OHX...HUN...
LAT...LON 36728643 37008583 37008520 36958482 36698470 35808475
35468497 35348594 35368655 36728643SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 7:11 PM CST | Severe Thunderstorm Watch | SPC | Clinton, Cumberland, Monroe | 3 hr |
| Feb 28, 8:45 PM CST | Mesoscale Discussion | SPC | Clinton, Cumberland, Monroe | 90 min |
| Feb 28, 6:27 PM CST | Mesoscale Discussion | SPC | Benton, Carroll, Cheatham, Chester, Crockett, Davidson and 29 more | 93 min |
Nearby
Mesoscale Discussions in Tennessee, 2021Mesoscale Discussions in Kentucky, 2021Every mesoscale discussion in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.