Alert archive / Alabama / Tornado Warnings in 2020

Tornado Warning 34, NWS Birmingham, AL

April 12, 2020Blount County, Alabama

NWS Birmingham, AL issued this tornado warning at Apr 12, 2020, 9:12 PM CDT for Blount County, Alabama. It was in force for 20 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 12, 2020, 9:12 PM CDT (02:12 UTC)
Expired: Apr 12, 2020, 9:32 PM CDT
In force: 20 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Blount County, AL

The radar

The Northeast Alabama radar (KHTX), 88 km from the middle of the area, began a volume at 02:15 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 was reported inside it

Time	Report	Where	Remark
Apr 12, 9:27 PM CDT	TORNADO	3 Se Strawberry, AL	AN EF-0 TORNADO BEGAN IN FAR NORTHERN BLOUNT COUNTY & CONTINUED INTO SOUTHERN MARSHALL COUNTY. MAXIMUM WINDS ALONG THE NWS-BMX PART OF THE PATH WERE AROUND 85 MPH, WITH A PATH LENGTH OF 1.94 MILES & WIDTH OF 150 YARDS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
Apr 12, 3:20 PM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 2.2 hours before the alert went out and 118 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 533 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 847 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 401 m²/s²
0-3 km storm-relative helicity: 509 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 8.4

Open this sounding in Storm Lab

The text

As transmitted.

851 
WFUS54 KBMX 130212
TORBMX
ALC009-130245-
/O.NEW.KBMX.TO.W.0034.200413T0212Z-200413T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Birmingham AL
912 PM CDT Sun Apr 12 2020

The National Weather Service in Birmingham has issued a

* Tornado Warning for...
  North central Blount County in central Alabama...

* Until 945 PM CDT.
    
* At 912 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Holly Pond, or 7 miles east of Cullman, moving
  northeast at 60 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...
  Strawberry.

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 3425 8644 3421 8641 3415 8658 3417 8657
      3419 8655 3420 8655 3425 8651 3425 8650
      3426 8645
TIME...MOT...LOC 0212Z 247DEG 53KT 3416 8672 

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

$$

17/KLAWS

1 follow-up statement

574 
WWUS54 KBMX 130232
SVSBMX

Severe Weather Statement
National Weather Service Birmingham AL
932 PM CDT Sun Apr 12 2020

ALC009-130242-
/O.CAN.KBMX.TO.W.0034.000000T0000Z-200413T0245Z/
Blount AL-
932 PM CDT Sun Apr 12 2020

...THE TORNADO WARNING FOR NORTH CENTRAL BLOUNT COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.  However gusty winds are
still possible with this thunderstorm.

A Tornado Watch remains in effect until midnight CDT for central
Alabama.

LAT...LON 3425 8644 3421 8641 3415 8658 3417 8657
      3419 8655 3420 8655 3425 8651 3425 8650
      3426 8645
TIME...MOT...LOC 0231Z 247DEG 53KT 3428 8639 

$$

17/KLAWS

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 12, 7:10 PM CDT	Tornado Warning	BMX	Greene	22 min
Apr 12, 7:14 PM CDT	Tornado Warning	BMX	Sumter	26 min
Apr 12, 7:16 PM CDT	Areal Flood Advisory	BMX	Cherokee, Etowah, St. Clair	6 hr
Apr 12, 8:08 PM CDT	Severe Thunderstorm Warning	BMX	Fayette, Walker	55 min
Apr 12, 8:14 PM CDT	Areal Flood Advisory	BMX	Fayette, Lamar, Marion, Walker, Winston	5 hr
Apr 12, 8:15 PM CDT	Tornado Warning	BMX	Walker, Winston	15 min
Apr 12, 8:25 PM CDT	Severe Thunderstorm Warning	BMX	Tuscaloosa	38 min
Apr 12, 8:29 PM CDT	Flash Flood Warning	BMX	Fayette, Greene, Jefferson, Pickens, Sumter, Tuscaloosa and 1 more	5 hr
Apr 12, 8:32 PM CDT	Tornado Warning	BMX	Jefferson, Tuscaloosa	21 min
Apr 12, 8:36 PM CDT	Severe Thunderstorm Warning	BMX	Blount, Jefferson	54 min
Apr 12, 8:36 PM CDT	Tornado Warning Tornado observed	BMX	Jefferson, Tuscaloosa	17 min
Apr 12, 8:49 PM CDT	River Flood Warning	BMX	Greene, Hale, Marengo, Sumter	5 days
Apr 12, 8:51 PM CDT	Severe Thunderstorm Warning	BMX	Jefferson	39 min
Apr 12, 8:52 PM CDT	River Flood Warning	BMX	Jefferson, Tuscaloosa, Walker	66 hr
Apr 12, 8:58 PM CDT	River Flood Warning	BMX	Greene, Hale, Marengo, Tuscaloosa	52 hr
Apr 12, 8:58 PM CDT	River Flood Warning	BMX	Greene, Hale, Marengo, Sumter, Tuscaloosa	61 hr
Apr 12, 9:19 PM CDT	Severe Thunderstorm Warning	BMX	Blount, Etowah, Jefferson, St. Clair, Shelby	71 min
Apr 12, 9:33 PM CDT	Tornado Warning	BMX	Marengo	27 min
Apr 12, 10:02 PM CDT	Severe Thunderstorm Warning	BMX	Dallas	27 min
Apr 12, 10:22 PM CDT	Flash Flood Warning	BMX	Blount, Calhoun, Cherokee, Etowah, St. Clair	4 hr
Apr 12, 10:24 PM CDT	Tornado Warning	BMX	Cherokee	36 min
Apr 12, 10:37 PM CDT	Severe Thunderstorm Warning	BMX	Lowndes, Montgomery	53 min
Apr 12, 10:47 PM CDT	Severe Thunderstorm Warning	BMX	Calhoun, Cherokee, Cleburne, Etowah	58 min
Apr 12, 10:53 PM CDT	Severe Thunderstorm Warning	BMX	Autauga, Elmore	43 min
Apr 12, 10:59 PM CDT	Severe Thunderstorm Warning	BMX	Chilton, Clay, Coosa, Shelby, Talladega, Tallapoosa	43 min
Apr 12, 11:01 PM CDT	Areal Flood Advisory	BMX	Greene, Hale, Pickens, Sumter	3 hr
Apr 12, 11:15 PM CDT	Severe Thunderstorm Warning	BMX	Bullock, Macon, Montgomery, Tallapoosa	60 min
Apr 12, 11:16 PM CDT	Special Weather Statement	BMX	Fayette, Lamar, Marion	74 min
Apr 12, 11:24 PM CDT	Areal Flood Warning	BMX	Fayette, Tuscaloosa, Walker	6 hr
Apr 12, 11:30 PM CDT	Severe Thunderstorm Warning	BMX	Lee, Russell	75 min
Apr 13, 12:08 AM CDT	Special Weather Statement	BMX	Barbour, Bullock, Pike	82 min
Apr 13, 12:11 AM CDT	Severe Thunderstorm Warning	BMX	Pike	64 min
Apr 13, 12:13 AM CDT	Areal Flood Advisory	BMX	Lowndes, Montgomery	3 hr
Apr 13, 12:18 AM CDT	Severe Thunderstorm Warning	BMX	Chambers	16 min
Apr 13, 12:43 AM CDT	Severe Thunderstorm Warning	BMX	Barbour, Bullock	53 min
Apr 13, 1:04 AM CDT	Areal Flood Advisory	BMX	Barbour, Bullock, Pike, Russell	3 hr
Apr 13, 1:29 AM CDT	High Wind Warning	BMX	Autauga, Calhoun, Chambers, Cherokee, Chilton, Clay and 10 more	3 hr
Apr 13, 1:29 AM CDT	Wind Advisory	BMX	Autauga, Calhoun, Chambers, Cherokee, Chilton, Clay and 10 more	7 hr
Apr 13, 2:25 AM CDT	River Flood Warning	BMX	Bibb, Jefferson, Shelby	18 hr
Apr 13, 4:08 AM CDT	Areal Flood Warning	BMX	Cherokee	12 hr
Apr 13, 7:43 AM CDT	Areal Flood Warning	BMX	Cherokee	3 days

Nearby

Tornado Warnings in Alabama, 2020 Every tornado warning in 2020 Tornadoes in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.