Alert archive / Alabama / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 393, NWS Birmingham, AL

August 9, 2011Dallas County, Lowndes County, Alabama

NWS Birmingham, AL issued this severe thunderstorm warning at Aug 9, 2011, 2:24 PM CDT for Dallas County, Lowndes County, Alabama. It was in force for 39 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: Aug 9, 2011, 2:24 PM CDT (19:24 UTC)
Expired: Aug 9, 2011, 3:03 PM CDT
In force: 39 min
Issued by: NWS Birmingham, AL
Area: Storm-based polygon

Counties Dallas County, AL, Lowndes County, AL

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 7.4 hours before the alert went out and 119 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: 2662 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 617 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -135 m²/s²
0-3 km storm-relative helicity: -84 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.

868 
WUUS54 KBMX 091924
SVRBMX
ALC047-085-092015-
/O.NEW.KBMX.SV.W.0393.110809T1924Z-110809T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BIRMINGHAM AL
224 PM CDT TUE AUG 9 2011

THE NATIONAL WEATHER SERVICE IN BIRMINGHAM HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN DALLAS COUNTY IN SOUTH CENTRAL ALABAMA...
  CENTRAL LOWNDES COUNTY IN SOUTH CENTRAL ALABAMA...

* UNTIL 315 PM CDT

* AT 223 PM CDT...THE NATIONAL WEATHER SERVICE INDICATED A LINE OF
  SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM
  MOSSES TO BELKNAP...AND MOVING SOUTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MOSSES...HAYNEVILLE...LOWNDESBORO...GORDONVILLE...BEECHWOOD...
  MACEDONIA...COLLIRENE AND FARMERSVILLE.

THIS INCLUDES...
INTERSTATE 65 EXIT NUMBERS 147 THROUGH 151...

WINDS OF 60 TO 70 MPH WILL BREAK LARGE TREE LIMBS AND CAUSE SOME
DAMAGE...ESPECIALLY TO SMALLER STRUCTURES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS.

&&

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

LAT...LON 3204 8687 3204 8694 3222 8718 3230 8663
      3217 8641 3207 8641 3198 8686
TIME...MOT...LOC 1923Z 299DEG 17KT 3223 8668 3219 8698

$$

27

3 follow-up statements

601 
WWUS54 KBMX 091937
SVSBMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
237 PM CDT TUE AUG 9 2011

ALC047-085-092015-
/O.CON.KBMX.SV.W.0393.000000T0000Z-110809T2015Z/
DALLAS AL-LOWNDES AL-
237 PM CDT TUE AUG 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL
LOWNDES AND SOUTHEASTERN DALLAS COUNTIES UNTIL 315 PM CDT...

AT 235 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DESTRUCTIVE WINDS
IN EXCESS OF 70 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM HAYNEVILLE TO 6 MILES SOUTHEAST OF BELKNAP...MOVING
SOUTHEAST AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  MOSSES...HAYNEVILLE...GORDONVILLE...BEECHWOOD...FARMERSVILLE...
  FOSTORIA...LETOHATCHEE...MOUNT WILLING AND CALHOUN.

THIS INCLUDES...
INTERSTATE 65 EXIT NUMBER 151...

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

LAT...LON 3204 8687 3204 8694 3218 8712 3228 8661
      3217 8641 3207 8641 3198 8686
TIME...MOT...LOC 1937Z 299DEG 17KT 3220 8661 3216 8691

$$

27

899 
WWUS54 KBMX 091952
SVSBMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
252 PM CDT TUE AUG 9 2011

ALC047-085-092015-
/O.CON.KBMX.SV.W.0393.000000T0000Z-110809T2015Z/
DALLAS AL-LOWNDES AL-
252 PM CDT TUE AUG 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL
LOWNDES AND SOUTHEASTERN DALLAS COUNTIES UNTIL 315 PM CDT...

AT 249 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DESTRUCTIVE WINDS
IN EXCESS OF 70 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM HAYNEVILLE TO 7 MILES WEST OF GORDONVILLE...MOVING
SOUTHEAST AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  BEECHWOOD...FOSTORIA...LETOHATCHEE...MOUNT WILLING AND CALHOUN.

THIS INCLUDES...
INTERSTATE 65 EXIT NUMBER 151...

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

LAT...LON 3204 8687 3204 8694 3213 8706 3223 8652
      3217 8641 3207 8641 3198 8686
TIME...MOT...LOC 1952Z 299DEG 17KT 3216 8654 3213 8684

$$

27

390 
WWUS54 KBMX 092003
SVSBMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
303 PM CDT TUE AUG 9 2011

ALC047-085-092013-
/O.CAN.KBMX.SV.W.0393.000000T0000Z-110809T2015Z/
DALLAS AL-LOWNDES AL-
303 PM CDT TUE AUG 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL LOWNDES AND
SOUTHEASTERN DALLAS COUNTIES IS CANCELLED...

THE LINE OF STORMS WHICH PROMPTED THE WARNING HAVE WEAKENED ACROSS 
THE WARNED AREA.

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

LAT...LON 3204 8687 3204 8694 3213 8706 3223 8652
      3217 8641 3207 8641 3198 8686
TIME...MOT...LOC 2003Z 299DEG 17KT 3214 8648 3210 8678

$$

27

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Birmingham, AL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 9, 12:45 PM CDT, 1 hour 39 minutes earlier.

Area forecast discussion, Aug 9, 12:45 PM CDT, 1 hour 39 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
1245 PM CDT TUE AUG 9 2011

.UPDATE...
18Z AVIATION.

&&

.DISCUSSION...

SHOWERS CONTINUE TO WEAKEN ACROSS THE NORTHWEST THIS MORNING IN
ASSOCIATION WITH AN MCV MOVING EWD ACROSS THE AREA. THINGS HAVE
BEEN PRETTY CALM SO FAR...BUT EXPECT STORMS TO START FIRING IN THE
NEXT COUPLE OF HOURS AS PEAK HEATING PROGRESSES. DIURNALLY DRIVEN
CONVECTION WILL BE A LITTLE SLOWER TO DEVELOP ACROSS THE NORTHERN
HALF AT FIRST..THANKS TO ONGOING CLOUD COVER. HOWEVER...THERE WILL
BE AT LEAST ONE IF NOT MORE WAVES/ROUNDS OF SHOWERS/STORMS THAT
WILL MOVE SEWD ACROSS THE CWA LATER TODAY AS A SHORTWAVE TROUGH
TRAVERSES THE AREA. SUFFICIENT INSTABILITY AND BULK SHEAR VALUES
OF 25 TO 30 THIS AFTN WILL LEAD TO THE POSSIBILITY OF SEVERE
STORMS ACROSS CENTRAL AL...AND SPC STILL HAS THE ENTIRE CWA IN A
SLIGHT RISK.

ONGOING FORECAST LOOKS ON TRACK FOR THE MOST PART...SO HAVE NOT
MADE ANY MAJOR CHANGES. DID MAKE SOME SLIGHT ADJUSTMENTS TO THE
POP AND SKY GRIDS. UPDATES ARE OUT.

19

&&

.AVIATION...
18Z TAF DISCUSSION.

DAYTIME HEATING AND OLD OUTFLOW BOUNDARIES...ALONG WITH AN UPPER
LEVEL SHORTWAVE PUSHING ACROSS THE AREA...WILL BE THE CONTRIBUTING
FACTORS TO SCATTERED TO NUMEROUS CONVECTION THIS AFTN/EVNG. COVERAGE
IS EXPECTED TO BE THE GREATEST ACROSS THE CENTRAL PORTIONS OF THE
CWA. TIMING WILL BE VERY DIFFICULT UNTIL TSTM COMPLEXES/LINES BEGIN
TO FORM. FOR NOW WILL KEEP PREVAILING VCTS IN FOR ALL TERMINALS THRU
02Z-04Z. SOME STORMS COULD BECOME SEVERE...PRODUCING DAMAGING
WINDS...HEAVY RAIN...AND FREQUENT CLOUD-TO-GROUND LIGHTNING.

ACTIVITY SHOULD BEGIN TO WEAKEN AND DIMINISH BY LATE EVNG...WITH
LEFTOVER CIRRUS OVERNIGHT. DUE TO CONTINUED LOW LEVEL MOISTURE AND
RAINFALL EXPECTED TODAY...IF SKIES CLEAR ENOUGH TONIGHT THEN PATCHY
FOG WILL LIKELY DEVELOP. THEREFORE...WILL KEEP MENTION OF MVFR VIS
IN FOR MOST SITES BETWEEN 10Z AND 12Z. RAIN CHANCES DECREASE
SIGNIFICANTLY ON WED AS SLIGHTLY DRIER AIR BRIEFLY MOVES INTO THE
REGION. FEW TO SCT CU WILL DEVELOP...BUT RAIN CHANCES ARE TOO LOW TO
MENTION ANY WX AT THIS TIME.

19

&&

.PRELIMINARY POINT TEMPS/POPS...
GADSDEN     90  70  93  72  92 /  60  30  20  20  30
ANNISTON    90  70  94  72  93 /  60  30  20  20  30
BIRMINGHAM  90  72  94  75  94 /  60  30  20  20  30
TUSCALOOSA  93  72  96  75  96 /  60  30  20  20  30
CALERA      91  72  94  74  93 /  60  30  20  20  30
AUBURN      93  72  95  75  94 /  50  30  20  20  30
MONTGOMERY  95  74  96  76  95 /  50  30  20  20  30
TROY        94  73  96  75  95 /  50  30  20  20  30

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

Hazardous weather outlook, Aug 9, 1:07 PM CDT, 1 hour 17 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
107 PM CDT TUE AUG 9 2011

ALZ011>015-017>050-101807-
AUTAUGA-BARBOUR-BIBB-BLOUNT-BULLOCK-CALHOUN-CHAMBERS-CHEROKEE-
CHILTON-CLAY-CLEBURNE-COOSA-DALLAS-ELMORE-ETOWAH-FAYETTE-GREENE-HALE-
JEFFERSON-LAMAR-LEE-LOWNDES-MACON-MARENGO-MARION-MONTGOMERY-PERRY-
PICKENS-PIKE-RANDOLPH-RUSSELL-SHELBY-ST CLAIR-SUMTER-TALLADEGA-
TALLAPOOSA-TUSCALOOSA-WALKER-WINSTON-
107 PM CDT TUE AUG 9 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE COUNTIES SERVED BY THE
NATIONAL WEATHER SERVICE OFFICE IN BIRMINGHAM.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS ALL OF CENTRAL ALABAMA
TODAY...MAINLY THROUGH 9 PM THIS EVENING. THE HAZARDOUS THREATS
INCLUDE DAMAGING STRAIGHT LINE WIND GUSTS...FREQUENT LIGHTNING AND
HEAVY RAIN.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT MAY BECOME
NECESSARY THIS AFTERNOON AND EVENING.

In the hours before

Special weather statement, Aug 9, 1:49 PM CDT, 35 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
149 PM CDT TUE AUG 9 2011

ALZ040-042-091930-
DALLAS AL-LOWNDES AL-
149 PM CDT TUE AUG 9 2011

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN LOWNDES AND SOUTHERN
DALLAS COUNTIES UNTIL 230 PM CDT...

AT 145 PM CDT...THE NATIONAL WEATHER SERVICE WAS TRACKING STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM SELMONT-WEST SELMONT TO
ORRVILLE...AND MOVING SOUTHEAST AT 20 MPH.

WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THESE STORMS...ALONG WITH
FREQUENT DANGEROUS LIGHTNING.

LOCATIONS IN OR NEAR THE PATH OF THESE STORMS INCLUDE...
  MOSSES...
  FIVE POINTS...
  TYLER...
  SARDIS...
  BENTON...

&&

LAT...LON 3206 8714 3231 8743 3242 8693 3237 8681
      3235 8681 3234 8682 3231 8681 3232 8678
      3235 8677 3222 8648
TIME...MOT...LOC 1849Z 296DEG 16KT 3234 8697 3229 8723

27

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 8, 7:39 PM CDT	Areal Flood Advisory	BMX	Autauga, Elmore	111 min
Aug 8, 7:48 PM CDT	Special Weather Statement	BMX	Lee	42 min
Aug 8, 8:13 PM CDT	Flash Flood Warning	BMX	Autauga, Elmore	48 min
Aug 8, 8:25 PM CDT	Flash Flood Warning	BMX	Autauga, Elmore, Lowndes, Montgomery	90 min
Aug 9, 1:49 PM CDT	Special Weather Statement	BMX	Dallas	41 min
Aug 9, 2:48 PM CDT	Special Weather Statement	BMX	Montgomery	42 min
Aug 9, 3:27 PM CDT	Special Weather Statement	BMX	Marengo	48 min
Aug 9, 4:15 PM CDT	Special Weather Statement	BMX	Pike	45 min
Aug 9, 4:26 PM CDT	Special Weather Statement	BMX	Barbour	49 min

Nearby

Severe Thunderstorm Warnings in Alabama, 2011 Every severe thunderstorm warning 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.