Alert archive / Louisiana / Tornado Watches in 2001

Tornado Watch 773

October 11, 20019 counties in Arkansas; 38 parishes in Louisiana; Newton County, Texas

The Storm Prediction Center issued this tornado watch at Oct 11, 2001, 10:00 AM CDT for 9 counties in Arkansas; 38 parishes in Louisiana; Newton County, Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Oct 11, 2001, 10:00 AM CDT (15:00 UTC)
Expired: Oct 11, 2001, 3:00 PM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 48 counties

Ashley County, AR, Bradley County, AR, Calhoun County, AR, Columbia County, AR, Drew County, AR, Lafayette County, AR, Nevada County, AR, Ouachita County, AR, Union County, AR, Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Iberia Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Union Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Newton County, TX

The radar

The Ft Polk radar (KPOE), 13 km from the middle of the area, began a volume at 15:03 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.

Warnings issued inside it

9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Oct 11, 10:25 AM CDT	Severe Thunderstorm Warning	SHV	Webster	50 min
Oct 11, 10:39 AM CDT	Severe Thunderstorm Warning	SHV	Bienville, Claiborne	51 min
Oct 11, 10:58 AM CDT	Tornado Warning	LCH	Vernon	62 min
Oct 11, 11:21 AM CDT	Severe Thunderstorm Warning	SHV	Lincoln, Union	39 min
Oct 11, 11:55 AM CDT	Severe Thunderstorm Warning	SHV	Ouachita	50 min
Oct 11, 12:03 PM CDT	Severe Thunderstorm Warning	LZK	Drew	42 min
Oct 11, 12:05 PM CDT	Severe Thunderstorm Warning	JAN	Morehouse	40 min
Oct 11, 12:33 PM CDT	Severe Thunderstorm Warning	SHV	Grant, LaSalle	42 min
Oct 11, 12:44 PM CDT	Severe Thunderstorm Warning	JAN	Morehouse	31 min

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 3.0 hours before the alert went out and 127 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: 1805 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 496 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 95 m²/s²
0-3 km storm-relative helicity: 120 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 5.4

Open this sounding in Storm Lab

The text

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

952 
WWUS9 KMKC 111448
SEL3  

SEL3  
MKC WW 111442
ARZ000-LAZ000-CWZ000-112000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 773
STORM PREDICTION CENTER NORMAN OK
942 AM CDT THU OCT 11 2001

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   SOUTHERN ARKANSAS                           
   MUCH OF LOUISIANA                          
   AND ADJACENT COASTAL WATERS                     

EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 1000 AM UNTIL
300 PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND WEST
OF A LINE FROM 35 MILES WEST SOUTHWEST OF INTRACOASTAL CITY
LOUISIANA TO 35 MILES NORTH NORTHEAST OF EL DORADO ARKANSAS.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...  CONTINUE...WW 772...

DISCUSSION...LINE OF STRONG THUNDERSTORMS EXTENDS FROM SOUTHWEST AR
INTO SOUTHEAST TX...WITH EMBEDDED BOWS/LEWPS AND ISOLATED
SUPERCELLS.  MOIST/UNSTABLE AIRMASS AHEAD OF LINE COUPLED WITH
SUFFICIENT VERTICAL SHEAR PROFILES SUGGEST THE THREAT OF SEVERE
STORMS PRODUCING DAMAGING WINDS AND ISOLATED TORNADOES.  

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 25035.

...HART

334,0912 293,0913 293,0934 334,0934

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 11, 3:00 PM CDT	Severe Thunderstorm Watch	SPC	Acadia, Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia and 15 more	5 hr
Oct 11, 6:00 PM CDT	Tornado Watch	SPC	Orleans, Saint Bernard, Saint Charles, Saint James, Saint John the Baptist, Saint Tammany and 2 more	4 hr
Oct 11, 8:00 AM CDT	Tornado Watch	SPC	Anderson, Angelina, Austin, Brazoria, Brazos, Burleson and 35 more	5 hr

Nearby

Tornado Watches in Louisiana, 2001 Tornado Watches in Arkansas, 2001 Tornado Watches in Texas, 2001 Every tornado watch in 2001

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; radar from the NEXRAD Level II archive.