Alert archive / Kentucky / Mesoscale Discussions in 2021
Mesoscale Discussion 134
The Storm Prediction Center issued this mesoscale discussion at Feb 28, 2021, 7:49 AM CST for 10 counties in Kentucky; 4 counties in Tennessee. It was in force for 116 min.
The area
The outline as issued.
The facts
- Issued
- Feb 28, 2021, 7:49 AM CST (13:49 UTC)
- Expired
- Feb 28, 2021, 9:45 AM CST
- In force
- 116 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Butler County, KY, Calloway County, KY, Christian County, KY, Graves County, KY, Logan County, KY, Marshall County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Warren County, KY, Henry County, TN, Obion County, TN, Stewart County, TN, Weakley County, TN
The radar
The Ft Campbell radar (KHPX), 59 km from the middle of the area, began a volume at 13:48 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 12:00Z, 1.8 hours before the alert went out and 134 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
- 50 J/kg
- Mixed-layer CIN
- -67 J/kg
- Mixed-layer LCL
- 695 m above ground
- 0-6 km bulk shear
- 62 kt
- 0-1 km storm-relative helicity
- 480 m²/s²
- 0-3 km storm-relative helicity
- 488 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
236
ACUS11 KWNS 281349
SWOMCD
SPC MCD 281349
KYZ000-TNZ000-281545-
Mesoscale Discussion 0134
NWS Storm Prediction Center Norman OK
0749 AM CST Sun Feb 28 2021
Areas affected...far northwest Tennessee into southwest Kentucky
Concerning...Severe potential...Watch unlikely
Valid 281349Z - 281545Z
Probability of Watch Issuance...20 percent
SUMMARY...A brief tornado cannot be ruled out with storms ongoing
over northwest Tennessee into southwest Kentucky over the next
couple hours.
DISCUSSION...An east/west oriented band of storms is currently
ongoing near a warm front, and situated near the northeastern extent
of the 500 J/kg MUCAPE axis where dewpoints have risen into the 60s
F.
While instability is not particularly strong, shear is quite
favorable for supercells and potentially tornadoes with effective
SRH (most of it concentrated in the lowest 1 km) over 300 m2/s2. The
12Z BNA sounding depicts a favorable hodograph, but meager buoyancy.
Modifying this sounding for a surface temperature closer to 70 F
would produce more favorable low-level buoyancy.
In the near term, a cell or two may strengthen within the ongoing
band of storms, with either damaging gusts or a brief tornado
possible.
..Jewell/Edwards.. 02/28/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LMK...OHX...PAH...MEG...
LAT...LON 36378800 36148913 36238933 36358937 36628903 36918843
37428658 37238624 36978630 36628693 36378800SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 1:01 PM CST | Mesoscale Discussion | SPC | Fulton | 119 min |
| Feb 28, 2:22 PM CST | Tornado Watch | SPC | Allen, Calloway, Christian, Fulton, Graves, Hickman and 5 more | 8 hr |
| Feb 28, 4:40 PM CST | Mesoscale Discussion | SPC | Calloway, Christian, Logan, Simpson, Todd, Trigg | 95 min |
| Feb 27, 6:06 PM CST | Mesoscale Discussion | SPC | Bedford, Benton, Cannon, Carroll, Cheatham, Chester and 28 more | 2 hr |
Nearby
Mesoscale Discussions in Kentucky, 2021Mesoscale Discussions in Tennessee, 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.