Alert archive / Louisiana / Tornado Warnings in 2012

Tornado Warning 37, NWS Shreveport, LA

December 9, 2012Bienville Parish, Natchitoches Parish, Winn Parish, Louisiana

NWS Shreveport, LA issued this tornado warning at Dec 9, 2012, 8:21 PM CST for Bienville Parish, Natchitoches Parish, Winn Parish, Louisiana. It was in force for 24 min. 1 report 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: Dec 9, 2012, 8:21 PM CST (02:21 UTC)
Expired: Dec 9, 2012, 8:45 PM CST
In force: 24 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

Counties Bienville Parish, LA, Natchitoches Parish, LA, Winn Parish, LA

The radar

The Shreveport radar (KSHV), 91 km from the middle of the area, began a volume at 02:23 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
Dec 9, 8:30 PM CST	TSTM WND DMG	10 S Bienville, LA	SEVERAL TREES DOWN AND LIMB DEBRIS NOTED IN THE SOUTHERN PART OF BIENVILLE PARSIH.

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
Dec 9, 5:47 PM CST	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 2.4 hours before the alert went out and 84 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: 928 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 874 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 161 m²/s²
0-3 km storm-relative helicity: 192 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 3.3

Open this sounding in Storm Lab

The text

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

943 
WFUS54 KSHV 100221
TORSHV
LAC013-069-127-100245-
/O.NEW.KSHV.TO.W.0037.121210T0221Z-121210T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
821 PM CST SUN DEC 9 2012

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN WINN PARISH IN NORTH CENTRAL LOUISIANA...
  SOUTHERN BIENVILLE PARISH IN NORTHWEST LOUISIANA...
  NORTH CENTRAL NATCHITOCHES PARISH IN NORTHWEST LOUISIANA...

* UNTIL 845 PM CST

* AT 819 PM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 6 MILES
  SOUTHWEST OF SALINE...OR 22 MILES WEST OF JONESBORO...MOVING
  NORTHEAST AT 30 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LUCKY
  AND FRIENDSHIP...

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.

&&

LAT...LON 3207 9306 3217 9311 3235 9291 3220 9280
      3215 9282 3214 9280
TIME...MOT...LOC 0221Z 243DEG 26KT 3214 9305

$$

20

1 follow-up statement

594 
WWUS54 KSHV 100233
SVSSHV

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
833 PM CST SUN DEC 9 2012

LAC069-127-100243-
/O.CAN.KSHV.TO.W.0037.000000T0000Z-121210T0245Z/
NATCHITOCHES LA-WINN LA-
833 PM CST SUN DEC 9 2012

...THE TORNADO WARNING FOR WINN AND NATCHITOCHES PARISHES IS
CANCELLED...

LAT...LON 3215 9282 3215 9283 3215 9296 3220 9301
      3235 9291 3220 9280
TIME...MOT...LOC 0233Z 243DEG 26KT 3218 9295

$$

LAC013-100245-
/O.CON.KSHV.TO.W.0037.000000T0000Z-121210T0245Z/
BIENVILLE LA-
833 PM CST SUN DEC 9 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 PM CST FOR BIENVILLE
PARISH...

AT 832 PM CST...USING DOPPLER RADAR...NATIONAL WEATHER SERVICE
METEOROLOGISTS CONTINUED TO DETECT A TORNADO.  THIS TORNADO WAS
LOCATED NEAR SALINE...OR 15 MILES WEST OF JONESBORO...MOVING
NORTHEAST AT 30 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
FRIENDSHIP

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING
QUARTER SIZE HAIL AND DESTRUCTIVE STRAIGHT LINE WINDS.

&&

LAT...LON 3215 9282 3215 9283 3215 9296 3220 9301
      3235 9291 3220 9280
TIME...MOT...LOC 0233Z 243DEG 26KT 3218 9295

$$

20

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 9, 8:07 PM CST	Severe Thunderstorm Warning	SHV	Bienville, Jackson, Natchitoches, Red River, Winn	38 min
Dec 9, 8:44 PM CST	Severe Thunderstorm Warning	SHV	Bienville, Jackson, Winn	46 min
Dec 9, 8:51 PM CST	Areal Flood Advisory	SHV	Sabine	3 hr
Dec 9, 9:10 PM CST	Severe Thunderstorm Warning	SHV	Caldwell, Jackson, Ouachita, Winn	50 min
Dec 9, 9:25 PM CST	Severe Thunderstorm Warning	SHV	Caldwell, Jackson, Ouachita	35 min
Dec 9, 11:53 PM CST	Lake Wind Advisory	SHV	Bossier, Caddo, Claiborne, Webster	11 hr

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.