Alert archive / Louisiana / Tornado Warnings in 2012

Tornado Warning 36, NWS Shreveport, LA

November 11, 2012Bossier Parish, Caddo Parish, Louisiana

NWS Shreveport, LA issued this tornado warning at Nov 11, 2012, 5:04 PM CST for Bossier Parish, Caddo Parish, Louisiana. It was in force for 41 min. 7 reports 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: Nov 11, 2012, 5:04 PM CST (23:04 UTC)
Expired: Nov 11, 2012, 5:45 PM CST
In force: 41 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

Counties Bossier Parish, LA, Caddo Parish, LA

The radar

The Shreveport radar (KSHV), 42 km from the middle of the area, began a volume at 23:05 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
Nov 11, 5:15 PM CST	TORNADO	Belcher, LA	A WEAK EF-0 TORNADO TOUCHED DOWN IN AN OPEN FIELD BETWEEN HIGHWAY 71 AND 3049 ON THE NORTH SIDE OF BELCHER. THIS TORNADO CONTINUED EAST NORTHEAST ACROSS OPEN FARMLAND TO NEAR THE END OF BELCHER RIVER ROAD AT ITS INTERSECTION WITH A LEVEE BEFORE CROSSING THE RE
Nov 11, 5:20 PM CST	TORNADO	4 Nnw Benton, LA	THIS IS A CONTINUATION OF THE WEAK EF-0 TORNADO FROM EASTERN CADDO PARISH. THIS TORNADO REMAINED SPORATICALLY ON THE GROUND CROSSING OLD PLAIN DEALING ROAD TO HIGHWAY 3 NEAR ALDEN BRIDGE. LARGE TREE LIMBS WERE SNAPPED OFF A FEW TREES ON PEACE LANE AS WELL AS O
Nov 11, 5:25 PM CST	TSTM WND DMG	1 Ne Belcher, LA	LARGE LIMBS WERE DOWNED ON BELCHER RIVER ROAD NEAR THE LEVEE.
Nov 11, 5:27 PM CST	TSTM WND DMG	4 Nnw Benton, LA	LARGE LIMBS WERE DOWNED ON PEACE LANE.
Nov 11, 5:31 PM CST	TSTM WND DMG	6 N Benton, LA	LARGE PINE TREE LIMBS WERE DOWNED ON THE WEST SIDE OF HIGHWAY 3 NEAR ALDEN BRIDGE ABOUT A HALF MILE SOUTH OF HIGHWAY 160.
Nov 11, 5:35 PM CST	TSTM WND DMG	2 Wnw Benton, LA	TREES DOWN ON OLD PLAIN DEALING ROAD
Nov 11, 5:40 PM CST	TSTM WND DMG	5 Ene Benton, LA	TREES DOWN ON BUTLER HILL ROAD

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
Nov 11, 12:53 PM CST	Tornado Watch	SPC	6 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 11.1 hours before the alert went out and 38 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: 14 J/kg
Mixed-layer CIN: -571 J/kg
Mixed-layer LCL: 641 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 389 m²/s²
0-3 km storm-relative helicity: 482 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.

646 
WFUS54 KSHV 112304
TORSHV
LAC015-017-112345-
/O.NEW.KSHV.TO.W.0036.121111T2304Z-121111T2345Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
504 PM CST SUN NOV 11 2012

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN BOSSIER PARISH IN NORTHWEST LOUISIANA...
  CENTRAL CADDO PARISH IN NORTHWEST LOUISIANA...

* UNTIL 545 PM CST

* AT 504 PM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO JUST SOUTHWEST OF 
  OIL CITY...OR 21 MILES NORTHWEST OF SHREVEPORT...MOVING NORTHEAST AT 
  35 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  BELCHER...GILLIAM...BENTON AND PLAIN DEALING...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WARNING MEANS THAT STRONG ROTATION HAS BEEN DETECTED IN THE
STORM. A TORNADO MAY ALREADY BE ON THE GROUND...OR IS EXPECTED TO
DEVELOP SHORTLY. IF YOU ARE IN THE PATH OF THIS DANGEROUS STORM...
MOVE INDOORS AND TO THE LOWEST LEVEL OF THE BUILDING. STAY AWAY FROM
WINDOWS. IF DRIVING...DO NOT SEEK SHELTER UNDER A HIGHWAY OVERPASS.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 3298 9358 3273 9349 3261 9404 3281 9404
TIME...MOT...LOC 2304Z 247DEG 32KT 3273 9398

$$

15

1 follow-up statement

772 
WWUS54 KSHV 112339
SVSSHV

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
539 PM CST SUN NOV 11 2012

LAC017-112347-
/O.CAN.KSHV.TO.W.0036.000000T0000Z-121111T2345Z/
CADDO LA-
539 PM CST SUN NOV 11 2012

...THE TORNADO WARNING FOR CADDO PARISH IS CANCELLED...

THE POTENTIALLY TORNADIC THUNDERSTORM HAS EXITED NORTHERN CADDO PARISH 
INTO NORTHERN BOSSIER PARISH. 

LAT...LON 3273 9349 3267 9377 3283 9380 3284 9378
      3286 9379 3298 9358
TIME...MOT...LOC 2337Z 247DEG 32KT 3276 9373

$$

LAC015-112345-
/O.CON.KSHV.TO.W.0036.000000T0000Z-121111T2345Z/
BOSSIER LA-
539 PM CST SUN NOV 11 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 545 PM CST FOR BOSSIER
PARISH...

AT 539 PM CST...WEATHER SERVICE METEOROLOGISTS CONTINUED TO DETECT A
SEVERE THUNDERSTORM WITH STRONG ROTATION.  THIS TORNADO WAS LOCATED
NEAR ALDEN BRIDGE...OR 4 MILES NORTH OF BENTON...MOVING NORTHEAST AT 
35 MPH. WHILE THE ROTATION HAS DIMINISHED IN THE LAST FEW MINUTES...THESE
STORMS WILL STILL BE CAPABLE OF PRODUCING DAMAGING STRAIGHT LINE WINDS 
TO 60 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROCKY
MOUNT...PLAIN DEALING AND IVAN

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WARNING MEANS THAT STRONG ROTATION HAS BEEN DETECTED IN THE
STORM. A TORNADO MAY ALREADY BE ON THE GROUND...OR IS EXPECTED TO
DEVELOP SHORTLY. IF YOU ARE IN THE PATH OF THIS DANGEROUS STORM...
MOVE INDOORS AND TO THE LOWEST LEVEL OF THE BUILDING. STAY AWAY FROM
WINDOWS. IF DRIVING...DO NOT SEEK SHELTER UNDER A HIGHWAY OVERPASS.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 3273 9349 3267 9377 3283 9380 3284 9378
      3286 9379 3298 9358
TIME...MOT...LOC 2337Z 247DEG 32KT 3276 9373

$$

15

The office that day

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

Issued	Product	Office	Counties	Lasted
Nov 11, 3:38 AM CST	Lake Wind Advisory	SHV	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	12 hr
Nov 11, 4:35 PM CST	Severe Thunderstorm Warning	SHV	Bossier, Caddo	40 min
Nov 11, 5:14 PM CST	Severe Thunderstorm Warning	SHV	Bossier, Caddo, Claiborne, Webster	61 min

Nearby

Tornado Warnings in Louisiana, 2012 Every tornado warning in 2012 Tornadoes in 2012

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.