Alert archive / Louisiana / Tornado Warnings in 2011

Tornado Warning 5, NWS Shreveport, LA

March 8, 2011LaSalle Parish, Louisiana

NWS Shreveport, LA issued this tornado warning at Mar 8, 2011, 9:37 PM CST for LaSalle Parish, Louisiana. It was in force for 23 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 8, 2011, 9:37 PM CST (03:37 UTC)
Expired: Mar 8, 2011, 10:00 PM CST
In force: 23 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

County LaSalle Parish, LA

The watch it was issued in

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

Issued	Product	Office	Lasted
Mar 8, 1:08 PM CST	Tornado Watch	SPC	9 hr
Mar 8, 7:37 PM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 3.6 hours before the alert went out and 179 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: 2444 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 506 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 195 m²/s²
0-3 km storm-relative helicity: 210 m²/s²
Significant tornado parameter: 2.5
Supercell composite: 12.5

Open this sounding in Storm Lab

The text

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

921 
WFUS54 KSHV 090337
TORSHV
LAC059-090400-
/O.NEW.KSHV.TO.W.0005.110309T0337Z-110309T0400Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
937 PM CST TUE MAR 8 2011

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN LA SALLE PARISH IN NORTH CENTRAL LOUISIANA...

* UNTIL 1000 PM CST

* AT 937 PM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 12 MILES
  SOUTHWEST OF CATAHOULA LAKE...OR 10 MILES EAST OF PINEVILLE...     
  MOVING NORTHEAST AT 45 MPH. A TORNADO WAS REPORTED WITH THIS STORM
  EARLIER NEAR ALEXANDRIA LOUISIANA. 

* THE TORNADO WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS OF THE
  INDICATED PARISH.

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.

&&

LAT...LON 3133 9209 3136 9208 3140 9214 3147 9216
      3148 9220 3150 9222 3150 9224 3169 9200
      3135 9200
TIME...MOT...LOC 0337Z 231DEG 38KT 3140 9223

$$

13

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 8, 10:00 PM CST	Severe Thunderstorm Warning	SHV	LaSalle	30 min
Mar 8, 11:10 PM CST	Flash Flood Warning	SHV	Grant, LaSalle	4 hr

Nearby

Tornado Warnings in Louisiana, 2011 Every tornado warning in 2011 Tornadoes 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.