Alert archive / Louisiana / Tornado Watches in 2008

Tornado Watch 91

March 3, 200814 counties in Arkansas; 39 parishes in Louisiana; 9 counties in Texas

The Storm Prediction Center issued this tornado watch at Mar 3, 2008, 10:36 AM CST for 14 counties in Arkansas; 39 parishes in Louisiana; 9 counties in Texas. It was in force for 9 hr.

The area

The outline as issued.

The facts

Issued
Mar 3, 2008, 10:36 AM CST (16:36 UTC)
Expired
Mar 3, 2008, 8:00 PM CST
In force
9 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
70 kt
All 62 counties

Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Lafayette County, AR, Lincoln 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, Caddo Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Saint Landry Parish, LA, Tensas Parish, LA, Union Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Hardin County, TX, Jasper County, TX, Jefferson County, TX, Newton County, TX, Orange County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Tyler County, TX

The radar

The Shreveport radar (KSHV), 95 km from the middle of the area, began a volume at 16:40 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
60%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Mar 3, 11:03 AM CSTSevere Thunderstorm WarningSHVCaddo, De Soto42 min
Mar 3, 1:51 PM CSTSevere Thunderstorm WarningLCHBeauregard, Vernon54 min
Mar 3, 2:31 PM CSTSevere Thunderstorm WarningJANAshley64 min
Mar 3, 2:39 PM CSTSevere Thunderstorm WarningSHVNatchitoches, Sabine51 min
Mar 3, 2:40 PM CSTSevere Thunderstorm WarningLCHAllen, Beauregard, Calcasieu, Rapides, Vernon50 min
Mar 3, 2:58 PM CSTTornado WarningLCHRapides, Vernon21 min
Mar 3, 4:55 PM CSTSevere Thunderstorm WarningJANEast Carroll, Madison50 min
Mar 3, 5:23 PM CSTSevere Thunderstorm WarningJANCatahoula, Concordia52 min
Mar 3, 5:56 PM CSTSevere Thunderstorm WarningLCHSaint Landry34 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 4.6 hours before the alert went out and 88 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, Shreveport, LA at 12:00Z on 2008-03-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 77 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 12:00Z on 2008-03-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 350 square meters per square second.19395878Sfc1 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
77 J/kg
Mixed-layer CIN
-167 J/kg
Mixed-layer LCL
667 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
350 m²/s²
0-3 km storm-relative helicity
489 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 031636
SEL1  
SPC WW 031636
ARZ000-LAZ000-TXZ000-CWZ000-040000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 91
NWS STORM PREDICTION CENTER NORMAN OK
1035 AM CST MON MAR 3 2008

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

       PARTS OF SOUTHERN ARKANSAS
       MUCH OF NORTHERN AND WESTERN LOUISIANA
       PARTS OF SOUTHEASTERN TEXAS
       COASTAL WATERS

EFFECTIVE THIS MONDAY MORNING AND EVENING FROM 1035 AM UNTIL 600
PM CST.

TORNADOES...HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES NORTHWEST OF
MONTICELLO ARKANSAS TO 35 MILES SOUTH SOUTHWEST OF LAKE CHARLES
LOUISIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

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 90...

DISCUSSION...INCREASING THREAT OF SUPERCELL DEVELOPMENT ASSOCIATED
WITH SQUALL LINE MOVING FROM ERN TX INTO LA. STRONG SHEAR PROFILES
AND INCREASING INSTABILITY COUPLED WITH APPROACH OF STRONG
TROUGH/WIND MAX FROM WRN TX WILL LEAD TO POTENTIAL FOR TORNADOES
BOTH WITH THE SQUALL LINE AND LATER THIS AFTERNOON FOR DISCRETE
STORMS AHEAD OF THE LINE.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24045.


...HALES

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 2, 8:23 PM CSTTornado WatchSPCCrawford, Franklin, Howard, Little River, Miller, Polk and 3 more8 hr
Mar 3, 1:36 AM CSTMesoscale DiscussionSPCHoward, Little River, Logan, Montgomery, Pike, Polk and 3 more54 min
Mar 3, 3:01 AM CSTMesoscale DiscussionSPCClark, Cleburne, Conway, Dallas, Faulkner, Garland and 20 more89 min
Mar 3, 5:21 AM CSTMesoscale DiscussionSPCLafayette, Miller84 min
Mar 3, 6:47 AM CSTSevere Thunderstorm WatchSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more6 hr
Mar 3, 10:18 AM CSTMesoscale DiscussionSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more87 min
Mar 3, 1:25 PM CSTMesoscale DiscussionSPCAshley, Chicot, Desha, Drew95 min
Mar 3, 2:25 PM CSTTornado WatchSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 19 more11 hr
Mar 3, 5:58 PM CSTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 19 more62 min
Mar 2, 6:05 PM CSTTornado WatchSPCBosque, Callahan, Collin, Comanche, Cooke, Dallas and 28 more8 hr
Mar 2, 8:01 PM CSTMesoscale DiscussionSPCCollin, Delta, Fannin, Franklin, Grayson, Hopkins and 4 more59 min
Mar 2, 11:04 PM CSTMesoscale DiscussionSPCBrown, Callahan, Coke, Coleman, Comanche, Concho and 12 more56 min
Mar 2, 11:27 PM CSTSevere Thunderstorm WatchSPCBrown, Coke, Coleman, Concho, Crockett, Irion and 13 more5 hr
Mar 3, 1:57 AM CSTTornado WatchSPCAnderson, Bell, Bosque, Collin, Comanche, Coryell and 26 more6 hr
Mar 3, 3:24 AM CSTMesoscale DiscussionSPCBastrop, Blanco, Brazos, Burleson, Burnet, Grimes and 9 more96 min

Nearby

Tornado Watches in Louisiana, 2008Tornado Watches in Arkansas, 2008Tornado Watches in Texas, 2008Every tornado watch in 2008

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.