Alert archive / Louisiana / Tornado Warnings in 2012

Tornado Warning 14, NWS Shreveport, LA

March 20, 2012Grant Parish, Natchitoches Parish, Louisiana

NWS Shreveport, LA issued this tornado warning at Mar 20, 2012, 10:20 PM CDT for Grant Parish, Natchitoches 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
Mar 20, 2012, 10:20 PM CDT (03:20 UTC)
Expired
Mar 20, 2012, 11:00 PM CDT
In force
40 min
Issued by
NWS Shreveport, LA
Area
Storm-based polygon

Counties Grant Parish, LA, Natchitoches Parish, LA

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 3.3 hours before the alert went out and 287 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 00:00Z on 2012-03-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 267 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 00:00Z on 2012-03-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
267 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1256 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
145 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.

742 
WFUS54 KSHV 210320
TORSHV
LAC043-069-210400-
/O.NEW.KSHV.TO.W.0014.120321T0320Z-120321T0400Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
1020 PM CDT TUE MAR 20 2012

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
  WEST CENTRAL GRANT PARISH IN NORTH CENTRAL LOUISIANA...
  SOUTHEASTERN NATCHITOCHES PARISH IN NORTHWEST LOUISIANA...

* UNTIL 1100 PM CDT

* AT 1020 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 21 MILES
  SOUTHWEST OF MONTGOMERY...OR 14 MILES NORTH OF SLAGLE...MOVING
  NORTHEAST AT 40 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  GORUM...BELLWOOD...CHOPIN...CLOUTIERVILLE...MELROSE...NATCHEZ...
  BERMUDA AND ALOHA.

LAT...LON 3136 9319 3176 9304 3174 9297 3171 9297
      3171 9288 3164 9268 3135 9302
TIME...MOT...LOC 0320Z 207DEG 33KT 3142 9307

$$

13
3 follow-up statements
572 
WWUS54 KSHV 210333
SVSSHV

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1033 PM CDT TUE MAR 20 2012

LAC043-069-210400-
/O.CON.KSHV.TO.W.0014.000000T0000Z-120321T0400Z/
NATCHITOCHES LA-GRANT LA-
1033 PM CDT TUE MAR 20 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT FOR GRANT
AND NATCHITOCHES PARISHES...

AT 1031 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A POSSIBLE TORNADO LOCATED NEAR BELLWOOD...OR 19 MILES 
NORTH OF SLAGLE...MOVING NORTHEAST AT 40 MPH. THIS STORM IS MOVING
TOWARDS MELROSE AND CLOUTIERVILLE. IF YOU LIVE IN THESE 
COMMUNITIES...TAKE COVER IMMEDIATELY. 

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.

&&

LAT...LON 3146 9315 3176 9304 3174 9297 3171 9297
      3171 9288 3164 9268 3140 9297
TIME...MOT...LOC 0331Z 207DEG 33KT 3151 9302

$$

13
058 
WWUS54 KSHV 210343
SVSSHV

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1043 PM CDT TUE MAR 20 2012

LAC043-069-210400-
/O.CON.KSHV.TO.W.0014.000000T0000Z-120321T0400Z/
NATCHITOCHES LA-GRANT LA-
1043 PM CDT TUE MAR 20 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT FOR GRANT
AND NATCHITOCHES PARISHES...

AT 1042 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A STORM CAPABLE OF PRODUCING A TORNADO AT ANY TIME. THIS 
STORM WAS LOCATED NEAR MELROSE...OR 14 MILES SOUTHEAST OF 
NATCHITOCHES...MOVING NORTHEAST AT 40 MPH. IF YOU LIVE IN MELROSE OR
MONTGOMERY...TAKE COVER IMMEDIATELY. 

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
NATCHEZ...BERMUDA...ALOHA AND MONTGOMERY

PRECAUTIONARY/PREPAREDNESS ACTIONS...

&&

LAT...LON 3146 9315 3176 9304 3174 9297 3171 9297
      3171 9288 3164 9268 3140 9297
TIME...MOT...LOC 0342Z 207DEG 33KT 3160 9296

$$

13
056 
WWUS54 KSHV 210349
SVSSHV

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1049 PM CDT TUE MAR 20 2012

LAC043-069-210400-
/O.CON.KSHV.TO.W.0014.000000T0000Z-120321T0400Z/
NATCHITOCHES LA-GRANT LA-
1049 PM CDT TUE MAR 20 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT FOR GRANT
AND NATCHITOCHES PARISHES...

AT 1048 PM CDT...DOPPLER RADAR CONTINUED TO INDICATE STRONG ROTATION 
WITH A THUNDERSTORM THAT COULD PRODUCE A TORNADO AT ANY TIME. THIS 
STORM WAS LOCATED JUST NORTH OF MELROSE TO BETWEEN MELROSE AND 
MONTGOMERY...MOVING NORTHEAST AT 40 MPH. IF YOU LIVE IN MONTGOMERY...
TAKE COVER IMMEDIATELY. 

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

LAT...LON 3158 9308 3176 9304 3174 9297 3171 9297
      3171 9288 3166 9278 3154 9294
TIME...MOT...LOC 0348Z 207DEG 33KT 3167 9294

$$

13

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 20, 8:55 PM CDTFlash Flood Warning EmergencySHVGrant, Natchitoches, Sabine, Winn10 hr
Mar 20, 9:02 PM CDTRiver Flood WarningSHVBienville, Bossier, Red River, Webster11 days
Mar 20, 9:03 PM CDTTornado WarningSHVNatchitoches27 min
Mar 20, 9:15 PM CDTFlash Flood WarningSHVBienville, De Soto, Red River9 hr
Mar 20, 9:24 PM CDTTornado WarningSHVNatchitoches36 min
Mar 20, 10:50 PM CDTFlash Flood WarningSHVBossier, Claiborne, Webster10 hr
Mar 21, 1:52 AM CDTFlash Flood WarningSHVBienville, Jackson, Lincoln, Union8 hr
Mar 21, 2:49 AM CDTTornado WarningSHVGrant, Winn26 min
Mar 21, 3:14 AM CDTTornado WarningSHVJackson, Winn46 min
Mar 21, 5:41 AM CDTTornado WarningSHVJackson, Winn34 min
Mar 21, 6:16 AM CDTFlash Flood WarningSHVBienville, Red River3 hr
Mar 21, 6:47 AM CDTFlash Flood Warning EmergencySHVGrant, Natchitoches, Red River, Sabine, Winn4 hr
Mar 21, 8:44 AM CDTFlash Flood WarningSHVClaiborne2 hr
Mar 21, 9:36 AM CDTFlash Flood WarningSHVUnion114 min
Mar 21, 10:51 AM CDTFlash Flood Warning EmergencySHVGrant, Natchitoches, Winn3 hr
Mar 21, 1:53 PM CDTAreal Flood WarningSHVNatchitoches6 hr

Nearby

Tornado Warnings in Louisiana, 2012Every tornado warning in 2012Tornadoes 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; the sounding from the Mesonet's radiosonde archive.