Alert archive / Alabama / Tornado Warnings in 2021

Tornado Warning 36, NWS Birmingham, AL

March 17, 20214 counties in Alabama

NWS Birmingham, AL issued this tornado warning at Mar 17, 2021, 5:42 PM CDT for 4 counties in Alabama. It was in force for 48 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Mar 17, 2021, 5:42 PM CDT (22:42 UTC)
Expired
Mar 17, 2021, 6:30 PM CDT
In force
48 min
Issued by
NWS Birmingham, AL
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Chilton County, AL, Coosa County, AL, Shelby County, AL, Talladega County, AL

The radar

The Birmingham radar (KBMX), 44 km from the middle of the area, began a volume at 22:42 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Mar 17, 11:36 AM CDTTornado Watch PDSSPC7 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 10.7 hours before the alert went out and 45 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.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 12:00Z on 2021-03-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 658 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Birmingham, AL at 12:00Z on 2021-03-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 169 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
658 J/kg
Mixed-layer CIN
-112 J/kg
Mixed-layer LCL
759 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
169 m²/s²
0-3 km storm-relative helicity
301 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

As transmitted.

459 
WFUS54 KBMX 172242
TORBMX
ALC021-037-117-121-172330-
/O.NEW.KBMX.TO.W.0036.210317T2242Z-210317T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Birmingham AL
542 PM CDT Wed Mar 17 2021

The National Weather Service in Birmingham has issued a

* Tornado Warning for...
  Southwestern Talladega County in east central Alabama...
  Northeastern Chilton County in central Alabama...
  Southeastern Shelby County in central Alabama...
  Northwestern Coosa County in east central Alabama...

* Until 630 PM CDT.
    
* At 542 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Gap Of The Mountain, or near Clanton, moving
  northeast at 40 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Sylacauga, Clanton, Childersburg, Wilsonville, Talladega Springs,
  Harpersville, Gap Of The Mountain, Strickland Crossroads, Marble
  Valley, Fayetteville, Lay Lake Dam, Lay Lake, Mitchell Lake,
  Alabama 4H Center, Shelby Shores, Waxahatchee Creek, Gantts Quarry,
  Highway 145 and CR 46, Paint Creek and I 65 Rest Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3320 8612 3319 8613 3320 8617 3316 8617
      3285 8656 3291 8669 3331 8642
TIME...MOT...LOC 2242Z 214DEG 33KT 3292 8659 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

87/GRANTHAM
2 follow-up statements
025 
WWUS54 KBMX 172257
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
557 PM CDT Wed Mar 17 2021

ALC021-037-117-121-172330-
/O.CON.KBMX.TO.W.0036.000000T0000Z-210317T2330Z/
Talladega AL-Chilton AL-Shelby AL-Coosa AL-
557 PM CDT Wed Mar 17 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
SOUTHWESTERN TALLADEGA...NORTHEASTERN CHILTON...SOUTHEASTERN SHELBY
AND NORTHWESTERN COOSA COUNTIES...
    
At 557 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Lay Lake, or near Talladega Springs, moving
northeast at 40 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Sylacauga, Childersburg, Wilsonville, Talladega Springs,
Harpersville, Strickland Crossroads, Marble Valley, Fayetteville, Lay
Lake Dam, Lay Lake, Mitchell Lake, Alabama 4H Center, Shelby Shores,
Waxahatchee Creek, Gantts Quarry, Highway 145 and CR 46, Paint Creek,
Kelley Branch, Varnons and Gaston Steam Plant.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3320 8612 3319 8613 3320 8617 3316 8617
      3292 8651 3301 8663 3331 8642
TIME...MOT...LOC 2257Z 214DEG 33KT 3304 8650 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

87/GRANTHAM
485 
WWUS54 KBMX 172321 RRA
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
621 PM CDT Wed Mar 17 2021

ALC021-037-117-121-172331-
/O.EXP.KBMX.TO.W.0036.000000T0000Z-210317T2330Z/
Talladega AL-Chilton AL-Shelby AL-Coosa AL-
621 PM CDT Wed Mar 17 2021

...THE TORNADO WARNING FOR SOUTHWESTERN TALLADEGA...NORTHEASTERN
CHILTON...SOUTHEASTERN SHELBY AND NORTHWESTERN COOSA COUNTIES WILL
EXPIRE AT 630 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 700 PM CDT for central and
east central Alabama.

LAT...LON 3320 8612 3319 8613 3320 8617 3316 8617
      3292 8651 3301 8663 3331 8642
TIME...MOT...LOC 2321Z 214DEG 33KT 3322 8636 

$$

87/GRANTHAM

The office that day

Everything else NWS Birmingham, AL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 16, 9:59 PM CDTSpecial Weather StatementBMXSumter46 min
Mar 16, 10:11 PM CDTSevere Thunderstorm WarningBMXSumter24 min
Mar 16, 10:38 PM CDTSpecial Weather StatementBMXHale37 min
Mar 17, 1:27 AM CDTDense Fog AdvisoryBMXAutauga, Barbour, Blount, Bullock, Calhoun, Chambers and 22 more6 hr
Mar 17, 11:18 AM CDTSpecial Weather StatementBMXJefferson27 min
Mar 17, 12:13 PM CDTTornado WarningBMXDallas47 min
Mar 17, 12:19 PM CDTAreal Flood AdvisoryBMXJefferson, Tuscaloosa2 hr
Mar 17, 12:21 PM CDTSevere Thunderstorm WarningBMXFayette, Lamar, Marion25 min
Mar 17, 12:41 PM CDTTornado WarningBMXAutauga64 min
Mar 17, 12:59 PM CDTTornado WarningBMXGreene, Sumter61 min
Mar 17, 1:18 PM CDTTornado WarningBMXAutauga, Chilton, Elmore57 min
Mar 17, 1:40 PM CDTSevere Thunderstorm WarningBMXPickens, Tuscaloosa28 min
Mar 17, 1:52 PM CDTTornado WarningBMXGreene, Hale, Marengo, Sumter41 min
Mar 17, 1:58 PM CDTTornado WarningBMXMarengo62 min
Mar 17, 1:59 PM CDTTornado WarningBMXGreene, Hale46 min
Mar 17, 2:02 PM CDTTornado Warning Tornado observedBMXChilton, Coosa58 min
Mar 17, 2:09 PM CDTTornado WarningBMXMarengo66 min
Mar 17, 2:14 PM CDTTornado WarningBMXJefferson, Walker61 min
Mar 17, 2:20 PM CDTTornado Warning Tornado observedBMXTuscaloosa40 min
Mar 17, 2:33 PM CDTTornado Warning Tornado observedBMXClay, Coosa, Talladega42 min
Mar 17, 2:44 PM CDTFlash Flood WarningBMXHale, Marengo, Perry2 hr
Mar 17, 2:47 PM CDTAreal Flood AdvisoryBMXGreene, Pickens, Sumter, Tuscaloosa2 hr
Mar 17, 2:48 PM CDTAreal Flood AdvisoryBMXBlount, Jefferson, Walker2 hr
Mar 17, 2:48 PM CDTAreal Flood AdvisoryBMXFayette, Lamar, Marion, Walker, Winston2 hr
Mar 17, 2:51 PM CDTFlash Flood WarningBMXJefferson2 hr
Mar 17, 2:53 PM CDTTornado Warning Tornado observedBMXTuscaloosa52 min
Mar 17, 2:54 PM CDTTornado WarningBMXDallas, Marengo, Perry66 min
Mar 17, 2:58 PM CDTTornado WarningBMXBlount, Jefferson34 min
Mar 17, 3:21 PM CDTTornado WarningBMXTuscaloosa54 min
Mar 17, 3:25 PM CDTFlash Flood WarningBMXTuscaloosa2 hr
Mar 17, 3:28 PM CDTAreal Flood AdvisoryBMXDallas, Perry2 hr
Mar 17, 3:34 PM CDTTornado Warning Tornado observedBMXJefferson, Walker56 min
Mar 17, 3:37 PM CDTTornado WarningBMXMarengo38 min
Mar 17, 3:58 PM CDTTornado Warning Tornado observedBMXJefferson47 min
Mar 17, 3:58 PM CDTTornado WarningBMXDallas, Perry47 min
Mar 17, 4:12 PM CDTTornado WarningBMXDallas48 min
Mar 17, 4:28 PM CDTTornado Warning Tornado observedBMXMarengo62 min
Mar 17, 4:36 PM CDTTornado Warning Tornado observedBMXJefferson54 min
Mar 17, 4:40 PM CDTTornado WarningBMXAutauga50 min
Mar 17, 4:43 PM CDTTornado WarningBMXDallas, Perry47 min
Mar 17, 5:00 PM CDTTornado WarningBMXChilton60 min
Mar 17, 5:09 PM CDTAreal Flood AdvisoryBMXJefferson111 min
Mar 17, 5:15 PM CDTTornado WarningBMXChilton60 min
Mar 17, 5:16 PM CDTTornado Warning Tornado observedBMXBlount44 min
Mar 17, 5:23 PM CDTTornado WarningBMXDallas, Marengo, Perry67 min
Mar 17, 5:26 PM CDTAreal Flood AdvisoryBMXAutauga, Chilton, Dallas, Hale, Marengo, Perry and 1 more3 hr
Mar 17, 5:41 PM CDTTornado WarningBMXMarengo23 min
Mar 17, 5:48 PM CDTTornado WarningBMXBlount42 min
Mar 17, 5:56 PM CDTAreal Flood AdvisoryBMXWalker, Winston44 min
Mar 17, 6:09 PM CDTTornado WarningBMXChilton, Coosa, Shelby, Talladega13 min
Mar 17, 6:40 PM CDTFlash Flood WarningBMXWalker, Winston3 hr
Mar 17, 6:48 PM CDTTornado WarningBMXDallas42 min

Nearby

Tornado Warnings in Alabama, 2021Every tornado warning in 2021Tornadoes 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.