Alert archive / Alabama / Tornado Warnings in 2011

Tornado Warning 39, NWS Birmingham, AL

April 11, 2011Bibb County, Hale County, Tuscaloosa County, Alabama

NWS Birmingham, AL issued this tornado warning at Apr 11, 2011, 6:43 PM CDT for Bibb County, Hale County, Tuscaloosa County, Alabama. It was in force for 14 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
Apr 11, 2011, 6:43 PM CDT (23:43 UTC)
Expired
Apr 11, 2011, 6:57 PM CDT
In force
14 min
Issued by
NWS Birmingham, AL
Area
Storm-based polygon

Counties Bibb County, AL, Hale County, AL, Tuscaloosa County, AL

The radar

The Birmingham radar (KBMX), 82 km from the middle of the area, began a volume at 23:43 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
Apr 11, 4:05 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 11.7 hours before the alert went out and 82 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 2011-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 9 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 2011-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 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
9 J/kg
Mixed-layer CIN
-684 J/kg
Mixed-layer LCL
606 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
179 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

296 
WFUS54 KBMX 112343 RRA
TORBMX
ALC007-065-125-120030-
/O.NEW.KBMX.TO.W.0039.110411T2343Z-110412T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
643 PM CDT MON APR 11 2011

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL BIBB COUNTY IN CENTRAL ALABAMA...
  NORTHERN HALE COUNTY IN WEST CENTRAL ALABAMA...
  SOUTH CENTRAL TUSCALOOSA COUNTY IN WEST CENTRAL ALABAMA...

* UNTIL 730 PM CDT

* AT 643 PM CDT...THE NATIONAL WEATHER SERVICE INDICATED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM
  WAS LOCATED NEAR KNOXVILLE...OR 13 MILES NORTHEAST OF EUTAW...AND
  MOVING EAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...
  BRENT...CENTREVILLE...MOUNDVILLE...LOW GAP...MERTZ...EOLINE...WEST
  CENTREVILLE...TALLADEGA NATIONAL FOREST...MOUNDVILLE AIRPORT AND
  MOUND STATE PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE
LOWEST FLOOR OF A STURDY BUILDING.

&&

TO REPORT SEVERE WEATHER...
CALL 1-800-856-0758.

LAT...LON 3293 8777 3294 8774 3298 8775 3298 8773
      3300 8771 3303 8771 3303 8778 3306 8778
      3312 8697 3288 8698 3288 8778
TIME...MOT...LOC 2343Z 265DEG 42KT 3298 8767

$$

27
1 follow-up statement
289 
WWUS54 KBMX 112357
SVSBMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
657 PM CDT MON APR 11 2011

ALC007-065-125-120008-
/O.CAN.KBMX.TO.W.0039.000000T0000Z-110412T0030Z/
HALE AL-BIBB AL-TUSCALOOSA AL-
657 PM CDT MON APR 11 2011

...THE TORNADO WARNING FOR SOUTH CENTRAL TUSCALOOSA...CENTRAL BIBB
AND NORTHERN HALE COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 11 PM CDT.

TO REPORT SEVERE WEATHER...CALL 1-800-856-0758.

LAT...LON 3293 8777 3294 8774 3298 8775 3298 8773
      3300 8771 3303 8771 3303 8778 3306 8778
      3312 8697 3288 8698 3288 8778
TIME...MOT...LOC 2358Z 265DEG 42KT 3299 8746

$$

27

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 11, 3:52 AM CDTWind AdvisoryBMXAutauga, Barbour, Bibb, Blount, Bullock, Calhoun and 33 more20 hr
Apr 11, 5:12 PM CDTSpecial Weather StatementBMXFayette, Lamar, Marion, Winston48 min
Apr 11, 5:36 PM CDTSevere Thunderstorm WarningBMXGreene, Pickens, Sumter, Tuscaloosa39 min
Apr 11, 5:42 PM CDTTornado WarningBMXFayette, Walker22 min
Apr 11, 6:08 PM CDTTornado WarningBMXGreene, Pickens, Tuscaloosa37 min
Apr 11, 6:13 PM CDTSevere Thunderstorm WarningBMXBibb, Greene, Jefferson, Pickens, Tuscaloosa47 min
Apr 11, 6:17 PM CDTSpecial Weather StatementBMXBlount, Walker43 min
Apr 11, 6:38 PM CDTTornado WarningBMXBibb, Tuscaloosa29 min
Apr 11, 6:43 PM CDTTornado WarningBMXGreene, Hale15 min
Apr 11, 6:48 PM CDTSevere Thunderstorm WarningBMXBibb, Chilton, Dallas, Greene, Hale, Jefferson and 5 more57 min
Apr 11, 6:52 PM CDTTornado WarningBMXBlount38 min
Apr 11, 6:53 PM CDTTornado WarningBMXJefferson, Tuscaloosa52 min

Nearby

Tornado Warnings in Alabama, 2011Every tornado warning in 2011Tornadoes in 2011

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.