Alert archive / Kentucky / Mesoscale Discussions in 2021
Mesoscale Discussion 267
The Storm Prediction Center issued this mesoscale discussion at Mar 25, 2021, 10:07 PM EDT for 4 states. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Mar 25, 2021, 10:07 PM EDT (02:07 UTC)
- Expired
- Mar 25, 2021, 11:30 PM EDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 51
All 89 counties
Bartholomew County, IN, Brown County, IN, Clark County, IN, Crawford County, IN, Dearborn County, IN, Decatur County, IN, Floyd County, IN, Harrison County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Lawrence County, IN, Ohio County, IN, Orange County, IN, Ripley County, IN, Scott County, IN, Switzerland County, IN, Washington County, IN, Adair County, KY, Allen County, KY, Anderson County, KY, Barren County, KY, Boone County, KY, Boyle County, KY, Breckinridge County, KY, Bullitt County, KY, Carroll County, KY, Casey County, KY, Clinton County, KY, Cumberland County, KY, Edmonson County, KY, Franklin County, KY, Gallatin County, KY, Garrard County, KY, Grant County, KY, Grayson County, KY, Green County, KY, Hardin County, KY, Hart County, KY, Henry County, KY, Jefferson County, KY, Jessamine County, KY, Kenton County, KY, Larue County, KY, Lincoln County, KY, Marion County, KY, Meade County, KY, Mercer County, KY, Metcalfe County, KY, Monroe County, KY, Nelson County, KY, Oldham County, KY, Owen County, KY, Pulaski County, KY, Russell County, KY, Scott County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Trimble County, KY, Warren County, KY, Washington County, KY, Wayne County, KY, Woodford County, KY, Hamilton County, OH, Bedford County, TN, Bledsoe County, TN, Cannon County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Jackson County, TN, Macon County, TN, Marshall County, TN, Morgan County, TN, Overton County, TN, Pickett County, TN, Putnam County, TN, Rhea County, TN, Rutherford County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Wilson County, TN
The radar
The Louisville radar (KLVX), 89 km from the middle of the area, began a volume at 02:07 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 00:00Z, 2.1 hours before the alert went out and 133 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
- 290 J/kg
- Mixed-layer CIN
- -73 J/kg
- Mixed-layer LCL
- 615 m above ground
- 0-6 km bulk shear
- 85 kt
- 0-1 km storm-relative helicity
- 657 m²/s²
- 0-3 km storm-relative helicity
- 631 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 7.4
The text
As transmitted.
483
ACUS11 KWNS 260207
SWOMCD
SPC MCD 260207
KYZ000-TNZ000-OHZ000-INZ000-260330-
Mesoscale Discussion 0267
NWS Storm Prediction Center Norman OK
0907 PM CDT Thu Mar 25 2021
Areas affected...Southern IN...Central/eastern KY...Middle/eastern
TN
Concerning...Tornado Watch 51...
Valid 260207Z - 260330Z
The severe weather threat for Tornado Watch 51 continues.
SUMMARY...The severe threat continues across WW 51, and some threat
may spread downstream of the watch prior to its 04Z expiration time.
A downstream watch may be needed soon.
DISCUSSION...At 02Z, the strongest convection across WW 51 remains
across portions of middle TN, where a threat for damaging wind and
perhaps a tornado or two will likely continue for the next 1-2
hours. Further north into KY and southern IN, where surface-based
buoyancy becomes increasingly limited, convection has struggled to
become organized, with occasional left-moving cells being the most
productive thus far. However, with very strong wind fields across
this region, the potential for remains for convection to organize
into bowing segments and/or embedded supercells, which would pose a
corresponding risk of damaging wind and perhaps a tornado. As this
convection spreads downstream out of WW 51, downstream watch
issuance may be needed soon.
..Dean/Grams.. 03/26/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MRX...JKL...ILN...LMK...OHX...IND...
LAT...LON 35478690 36638653 38668655 39108649 39498587 39358451
38198448 35698457 35438530 35428654 35478690SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 25, 10:26 PM EDT | Tornado Watch | SPC | Adair, Boyle, Casey, Clinton, Cumberland, Estill and 19 more | 2 hr |
| Mar 25, 8:00 PM EDT | Mesoscale Discussion | SPC | Franklin, Giles, Lawrence, Lincoln, Wayne | 30 min |
| Mar 25, 8:36 PM EDT | Mesoscale Discussion | SPC | Bedford, Cannon, Coffee, Davidson, DeKalb, Grundy and 11 more | 84 min |
| Mar 25, 8:57 PM EDT | Tornado Watch | SPC | Franklin, Giles, Lawrence, Lincoln, Moore, Wayne | 3 hr |
Nearby
Mesoscale Discussions in Kentucky, 2021Mesoscale Discussions in Tennessee, 2021Mesoscale Discussions in Indiana, 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.