Alert archive / Alabama / Tornado Warnings in 2011

Tornado Warning 112, NWS Mobile, AL

September 4, 2011Washington County, Alabama

NWS Mobile, AL issued this tornado warning at Sep 4, 2011, 12:58 PM CDT for Washington County, Alabama. It was in force for 62 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
Sep 4, 2011, 12:58 PM CDT (17:58 UTC)
Expired
Sep 4, 2011, 2:00 PM CDT
In force
62 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

County Washington County, AL

The radar

The Mobile radar (KMOB), 97 km from the middle of the area, began a volume at 17:58 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
Sep 4, 5:05 AM CDTTornado WatchSPC11 hr

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 6.0 hours before the alert went out and 197 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, Jackson, MS at 12:00Z on 2011-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 307 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, Jackson, MS at 12:00Z on 2011-09-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 279 square meters per square second.193958Sfc1 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
307 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
490 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
279 m²/s²
0-3 km storm-relative helicity
278 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.7

Open this sounding in Storm Lab

The text

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

979 
WFUS54 KMOB 041758
TORMOB
ALC129-041900-
/O.NEW.KMOB.TO.W.0112.110904T1758Z-110904T1900Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE MOBILE AL
1258 PM CDT SUN SEP 4 2011

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL WASHINGTON COUNTY IN SOUTHWEST ALABAMA...

* UNTIL 200 PM CDT

* AT 1253 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 11 MILES SOUTH
  OF CHATOM...OR 5 MILES EAST OF TIBBIE...MOVING NORTH AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  HOBSON...             CHATOM...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF IN MANUFACTURED HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
STURDY SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST
DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 400 PM CDT SUNDAY AFTERNOON
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

&&

LAT...LON 3168 8829 3168 8809 3135 8814 3135 8822
TIME...MOT...LOC 1758Z 178DEG 21KT 3140 8817

$$
2 follow-up statements
310 
WWUS54 KMOB 041835
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
135 PM CDT SUN SEP 4 2011

ALC129-041900-
/O.CON.KMOB.TO.W.0112.000000T0000Z-110904T1900Z/
WASHINGTON AL-
135 PM CDT SUN SEP 4 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 200 PM CDT FOR NORTH
CENTRAL WASHINGTON COUNTY...

AT 130 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A TORNADO.  THIS POSSIBLE TORNADO WAS LOCATED JUST NORTH OF 
CHATOM...MOVING NORTH AT 25 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
BIGBEE...KOENTON...FRANKVILLE AND BASHI

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
STURDY SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST
DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 400 PM CDT SUNDAY AFTERNOON
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

&&

LAT...LON 3168 8829 3168 8809 3146 8813 3146 8824
TIME...MOT...LOC 1834Z 178DEG 21KT 3157 8818

$$
105 
WWUS54 KMOB 041855
SVSMOB

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
155 PM CDT SUN SEP 4 2011

ALC129-041905-
/O.EXP.KMOB.TO.W.0112.000000T0000Z-110904T1900Z/
WASHINGTON AL-
155 PM CDT SUN SEP 4 2011

...THE TORNADO WARNING FOR NORTH CENTRAL WASHINGTON COUNTY WILL
EXPIRE AT 200 PM CDT...

THE STORM THAT PROMPTED THE WARNING HAS WEAKENED AND THEREFORE...THE 
WARNING WILL BE ALLOWED TO EXPIRE.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 400 PM CDT SUNDAY AFTERNOON
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

LAT...LON 3168 8829 3168 8809 3146 8813 3146 8824
TIME...MOT...LOC 1855Z 178DEG 21KT 3169 8819

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 3, 7:53 PM CDTAreal Flood WarningMOBBaldwin, Mobile6 hr
Sep 3, 8:02 PM CDTSpecial Marine WarningMOB43 min
Sep 3, 8:24 PM CDTSpecial Marine WarningMOB51 min
Sep 3, 9:11 PM CDTRiver Flood WarningMOBCovington, Escambia12 hr
Sep 3, 10:34 PM CDTSpecial Marine WarningMOB41 min
Sep 3, 11:11 PM CDTTornado WarningMOBMobile64 min
Sep 3, 11:58 PM CDTTornado WarningMOBMobile62 min
Sep 4, 12:13 AM CDTSpecial Marine WarningMOB2 hr
Sep 4, 12:59 AM CDTTornado WarningMOBMobile61 min
Sep 4, 1:14 AM CDTFlash Flood WarningMOBMobile3 hr
Sep 4, 1:40 AM CDTFlash Flood WarningMOBMobile3 hr
Sep 4, 1:59 AM CDTTornado WarningMOBMobile45 min
Sep 4, 2:16 AM CDTSpecial Marine WarningMOB119 min
Sep 4, 2:46 AM CDTTornado WarningMOBBaldwin59 min
Sep 4, 3:16 AM CDTSpecial Marine WarningMOB119 min
Sep 4, 3:57 AM CDTTornado WarningMOBBaldwin42 min
Sep 4, 4:49 AM CDTSpecial Marine WarningMOB86 min
Sep 4, 5:36 AM CDTFlash Flood WarningMOBCovington, Escambia3 hr
Sep 4, 5:51 AM CDTSpecial Marine WarningMOB114 min
Sep 4, 9:42 AM CDTSpecial Marine WarningMOB33 min
Sep 4, 9:59 AM CDTRiver Flood WarningMOBChoctaw, Clarke, Washington4 days
Sep 4, 9:59 AM CDTRiver Flood WarningMOBChoctaw, Clarke, Washington5 days
Sep 4, 10:43 AM CDTSpecial Marine WarningMOB47 min
Sep 4, 10:44 AM CDTSpecial Marine WarningMOB46 min
Sep 4, 11:29 AM CDTSpecial Marine WarningMOB46 min
Sep 4, 11:46 AM CDTTornado WarningMOBBaldwin, Mobile19 min
Sep 4, 12:12 PM CDTTornado WarningMOBWashington63 min
Sep 4, 1:20 PM CDTTornado WarningMOBClarke, Washington55 min
Sep 4, 4:01 PM CDTTornado WarningMOBChoctaw, Clarke59 min
Sep 4, 4:09 PM CDTTornado WarningMOBWashington36 min
Sep 4, 4:15 PM CDTTornado WarningMOBBaldwin, Escambia60 min
Sep 4, 4:28 PM CDTTornado WarningMOBBaldwin49 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.