Alert archive / Alabama / Tornado Watches in 2021
Tornado Watch 65
The Storm Prediction Center issued this tornado watch at Mar 27, 2021, 11:27 PM CDT for 17 counties in Alabama; 12 counties in Tennessee. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 27, 2021, 11:27 PM CDT (04:27 UTC)
- Expired
- Mar 28, 2021, 7:00 AM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 75 kt
All 29 counties
Blount County, AL, Colbert County, AL, Cullman County, AL, DeKalb County, AL, Fayette County, AL, Franklin County, AL, Jackson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Walker County, AL, Winston County, AL, Bedford County, TN, Coffee County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hickman County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Marshall County, TN, Maury County, TN, Moore County, TN
The radar
The Northeast Alabama radar (KHTX), 71 km from the middle of the area, began a volume at 04:28 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 70%
- One or more gusts of 65 knots or more
- 60%
- Ten or more severe hail reports
- 10%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
19 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 28, 12:17 AM CDT | Severe Thunderstorm Warning | OHX | Hickman, Lawrence, Lewis, Perry, Wayne | 43 min |
| Mar 28, 12:31 AM CDT | Severe Thunderstorm Warning | HUN | Colbert, Lauderdale | 44 min |
| Mar 28, 12:54 AM CDT | Severe Thunderstorm Warning | OHX | Giles, Hickman, Lawrence, Lewis, Marshall, Maury and 2 more | 36 min |
| Mar 28, 1:25 AM CDT | Severe Thunderstorm Warning | OHX | Bedford, Cannon, Coffee, Giles, Lawrence, Marshall and 3 more | 35 min |
| Mar 28, 1:52 AM CDT | Flash Flood Warning | HUN | Lauderdale | 3 hr |
| Mar 28, 1:54 AM CDT | Severe Thunderstorm Warning | OHX | Bedford, Giles, Lawrence, Marshall | 36 min |
| Mar 28, 2:47 AM CDT | Severe Thunderstorm Warning | BMX | Marion | 43 min |
| Mar 28, 3:09 AM CDT | Severe Thunderstorm Warning | HUN | Colbert, Franklin, Lawrence | 36 min |
| Mar 28, 3:34 AM CDT | Severe Thunderstorm Warning | HUN | Lawrence, Limestone, Morgan | 26 min |
| Mar 28, 3:47 AM CDT | Severe Thunderstorm Warning | BMX | Fayette, Lamar, Marion | 58 min |
| Mar 28, 3:58 AM CDT | Severe Thunderstorm Warning | HUN | Jackson, Limestone, Madison, Morgan | 47 min |
| Mar 28, 4:26 AM CDT | Severe Thunderstorm Warning | HUN | Jackson | 34 min |
| Mar 28, 4:32 AM CDT | Severe Thunderstorm Warning | BMX | Fayette, Walker, Winston | 47 min |
| Mar 28, 4:46 AM CDT | Severe Thunderstorm Warning | HUN | Jackson, Limestone, Madison, Morgan | 44 min |
| Mar 28, 5:02 AM CDT | Severe Thunderstorm Warning | HUN | Cullman | 28 min |
| Mar 28, 5:21 AM CDT | Severe Thunderstorm Warning | HUN | Jackson | 24 min |
| Mar 28, 5:30 AM CDT | Severe Thunderstorm Warning | HUN | Cullman | 30 min |
| Mar 28, 5:57 AM CDT | Severe Thunderstorm Warning | HUN | DeKalb, Marshall | 33 min |
| Mar 28, 6:13 AM CDT | Severe Thunderstorm Warning | BMX | Blount, Jefferson, Walker | 62 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Nashville Metro, TN (KBNA), launched 00:00Z, 4.5 hours before the alert went out and 139 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
- 200 J/kg
- Mixed-layer CIN
- -290 J/kg
- Mixed-layer LCL
- 839 m above ground
- 0-6 km bulk shear
- 62 kt
- 0-1 km storm-relative helicity
- 341 m²/s²
- 0-3 km storm-relative helicity
- 458 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.8
The text
As transmitted.
842
WWUS20 KWNS 280425
SEL5
SPC WW 280425
ALZ000-TNZ000-281100-
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 65
NWS Storm Prediction Center Norman OK
1125 PM CDT Sat Mar 27 2021
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Northern Alabama
Southern Middle Tennessee
* Effective this Saturday night and Sunday morning from 1125 PM
until 600 AM CDT.
* Primary threats include...
A couple tornadoes possible
Scattered damaging winds and isolated significant gusts to 85
mph likely
SUMMARY...Fast-moving bowing QLCS should spread across southern
Middle Tennessee and far northern Alabama. A trailing QLCS with
embedded bows may spread east from northern Mississippi across the
rest of northern Alabama through the pre-dawn hours.
The tornado watch area is approximately along and 70 statute miles
east and west of a line from 75 miles north of Huntsville AL to 75
miles south of Muscle Shoals AL. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 64...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 1 inch. Extreme turbulence and surface wind
gusts to 75 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 25050.
...GramsSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 27, 10:45 PM CDT | Mesoscale Discussion | SPC | Colbert, Franklin, Lauderdale, Lawrence, Limestone, Madison and 3 more | 90 min |
| Mar 28, 1:25 AM CDT | Mesoscale Discussion | SPC | Jackson | 2 hr |
| Mar 28, 1:57 AM CDT | Mesoscale Discussion | SPC | Blount, Colbert, Cullman, DeKalb, Etowah, Fayette and 11 more | 93 min |
| Mar 28, 4:56 AM CDT | Mesoscale Discussion | SPC | Blount, Cullman, DeKalb, Etowah, Marshall, Walker | 94 min |
| Mar 28, 5:10 AM CDT | Severe Thunderstorm Watch | SPC | Bibb, Blount, Calhoun, Cherokee, Clay, Cleburne and 12 more | 5 hr |
| Mar 28, 7:29 AM CDT | Mesoscale Discussion | SPC | Calhoun, Cleburne, Talladega | 91 min |
| Mar 28, 9:14 AM CDT | Mesoscale Discussion | SPC | Autauga, Chambers, Chilton, Clay, Coosa, Dallas and 6 more | 61 min |
| Mar 27, 8:42 PM CDT | Mesoscale Discussion | SPC | Alcorn, Benton, Calhoun, Carroll, Chickasaw, Coahoma and 26 more | 93 min |
| Mar 27, 9:01 PM CDT | Tornado Watch | SPC | Alcorn, Attala, Benton, Bolivar, Calhoun, Carroll and 33 more | 7 hr |
| Mar 28, 2:07 AM CDT | Severe Thunderstorm Watch | SPC | Anderson, Bledsoe, Blount, Bradley, Cumberland, Hamilton and 14 more | 6 hr |
Nearby
Tornado Watches in Alabama, 2021Tornado Watches in Tennessee, 2021Every tornado watch 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.