Alert archive / Louisiana / Tornado Warnings in 2011

Tornado Warning 151, NWS New Orleans, LA

September 4, 2011Saint Tammany Parish, Washington Parish, Louisiana

NWS New Orleans, LA issued this tornado warning at Sep 4, 2011, 6:20 PM CDT for Saint Tammany Parish, Washington Parish, Louisiana. It was in force for 40 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, 6:20 PM CDT (23:20 UTC)
Expired
Sep 4, 2011, 7:00 PM CDT
In force
40 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon

Counties Saint Tammany Parish, LA, Washington Parish, LA

The watch it was issued in

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

IssuedProductOfficeLasted
Sep 4, 3:47 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 11.3 hours before the alert went out and 67 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, Slidell Radar S, LA at 12:00Z on 2011-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2528 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, Slidell Radar S, LA at 12:00Z on 2011-09-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 249 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
2528 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
473 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
249 m²/s²
0-3 km storm-relative helicity
287 m²/s²
Significant tornado parameter
3.0
Supercell composite
18.9

Open this sounding in Storm Lab

The text

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

631 
WFUS54 KLIX 042320
TORLIX
LAC103-117-050000-
/O.NEW.KLIX.TO.W.0151.110904T2320Z-110905T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
620 PM CDT SUN SEP 4 2011

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL ST. TAMMANY PARISH IN SOUTHEAST LOUISIANA...
  EASTERN WASHINGTON PARISH IN SOUTHEAST LOUISIANA...
  THIS INCLUDES THE CITY OF BOGALUSA...

* UNTIL 700 PM CDT

* AT 616 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED   
  A RAIN SQUALL CAPABLE OF PRODUCING A TORNADO 8 MILES SOUTHWEST OF  
  BUSH...OR 7 MILES NORTHEAST OF COVINGTON...MOVING NORTH AT 40 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO   
SUN...ENON AND VARNADO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. TAKE COVER NOW! IF YOU WAIT
TO SEE OR HEAR IT COMING...IT MAY BE TOO LATE TO GET TO A SAFE PLACE.

THE SAFEST PLACE TO BE DURING A TORNADO IS UNDER A WORKBENCH OR OTHER
PIECE OF STURDY FURNITURE. SEEK SHELTER ON THE LOWEST FLOOR OF THE
BUILDING IN AN INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE
BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM
WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL 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 1000 PM CDT SUNDAY EVENING
FOR SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI.

&&

LAT...LON 3100 9004 3100 8978 3048 8994 3051 9014
TIME...MOT...LOC 2320Z 191DEG 35KT 3059 9002

$$

98/SO
1 follow-up statement
500 
WWUS54 KLIX 042338
SVSLIX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
638 PM CDT SUN SEP 4 2011

LAC103-042347-
/O.CAN.KLIX.TO.W.0151.000000T0000Z-110905T0000Z/
ST. TAMMANY LA-
638 PM CDT SUN SEP 4 2011

...THE TORNADO WARNING FOR NORTH CENTRAL ST. TAMMANY PARISH IS
CANCELLED...

THE STORM THAT PROMPTED THE WARNING HAS MOVED INTO WASHINGTON PARISH.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT SUNDAY EVENING
FOR SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI.

LAT...LON 3100 8978 3066 8988 3067 9000 3068 9010
      3100 9004
TIME...MOT...LOC 2337Z 187DEG 26KT 3073 9002

$$

LAC117-050000-
/O.CON.KLIX.TO.W.0151.000000T0000Z-110905T0000Z/
WASHINGTON LA-
638 PM CDT SUN SEP 4 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR EASTERN
WASHINGTON PARISH...

AT 636 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO 
DETECT A TORNADO. THE TORNADO WAS LOCATED NEAR ENON...OR 10 MILES 
SOUTHWEST OF BOGALUSA...MOVING NORTH AT 30 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO VARNADO
AND ANGIE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS UNDER A WORKBENCH OR OTHER
PIECE OF STURDY FURNITURE. SEEK SHELTER ON THE LOWEST FLOOR OF THE
BUILDING IN AN INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE
BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM
WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL 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 1000 PM CDT SUNDAY EVENING
FOR SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI.

&&

LAT...LON 3100 8978 3066 8988 3067 9000 3068 9010
      3100 9004
TIME...MOT...LOC 2337Z 187DEG 26KT 3073 9002

$$

98/SO

The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 3, 7:49 PM CDTSpecial Marine WarningLIX56 min
Sep 3, 8:32 PM CDTTornado WarningLIXPlaquemines, Saint Bernard28 min
Sep 3, 8:37 PM CDTSpecial Marine WarningLIX53 min
Sep 3, 9:28 PM CDTSpecial Marine WarningLIX32 min
Sep 3, 9:37 PM CDTSpecial Marine WarningLIX23 min
Sep 3, 9:56 PM CDTTornado WarningLIXSaint Tammany34 min
Sep 3, 11:21 PM CDTRiver Flood WarningLIXAscension, Livingston4 days
Sep 4, 2:54 AM CDTSpecial Marine WarningLIX36 min
Sep 4, 4:20 AM CDTSpecial Marine WarningLIX25 min
Sep 4, 4:42 AM CDTSpecial Marine WarningLIX33 min
Sep 4, 6:23 AM CDTAreal Flood AdvisoryLIXJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 1 more112 min
Sep 4, 8:05 AM CDTFlash Flood WarningLIXAssumption, Lafourche, Terrebonne4 hr
Sep 4, 11:00 AM CDTRiver Flood WarningLIXSaint Tammany, Washington16 days
Sep 4, 11:00 AM CDTRiver Flood WarningLIXSaint Tammany18 days
Sep 4, 11:15 AM CDTFlash Flood WarningLIXPlaquemines3 hr
Sep 4, 11:34 AM CDTSpecial Marine WarningLIX26 min
Sep 4, 12:10 PM CDTSpecial Marine WarningLIX35 min
Sep 4, 1:22 PM CDTSpecial Marine WarningLIX23 min
Sep 4, 2:32 PM CDTTornado WarningLIXTangipahoa, Washington28 min
Sep 4, 2:59 PM CDTTornado WarningLIXTangipahoa, Washington46 min
Sep 4, 3:43 PM CDTTornado WarningLIXTangipahoa, Washington47 min
Sep 4, 5:27 PM CDTFlash Flood WarningLIXPointe Coupee, West Feliciana3 hr

Nearby

Tornado Warnings in Louisiana, 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.