Alert archive / Louisiana / Tornado Watches in 2002

Tornado Watch 791

December 19, 20024 states

The Storm Prediction Center issued this tornado watch at Dec 19, 2002, 2:25 AM CST for 4 states. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Dec 19, 2002, 2:25 AM CST (08:25 UTC)
Expired
Dec 19, 2002, 10:00 AM CST
In force
8 hr
Issued by
the Storm Prediction Center
All 48 counties

Ashley County, AR, Bradley County, AR, Chicot County, AR, Union County, AR, Avoyelles Parish, LA, Bienville Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson 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, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Attala County, MS, Carroll County, MS, Choctaw County, MS, Claiborne County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Leflore County, MS, Montgomery County, MS, Sharkey County, MS, Warren County, MS, Washington County, MS, Yazoo County, MS, Angelina County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Trinity County, TX

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Dec 19, 2:48 AM CSTSevere Thunderstorm WarningJANAshley47 min
Dec 19, 3:18 AM CSTTornado WarningSHVBienville, Lincoln42 min
Dec 19, 3:46 AM CSTFlash Flood WarningLZKArkansas, Bradley, Calhoun, Desha, Drew4 hr
Dec 19, 3:53 AM CSTTornado WarningSHVBienville, Natchitoches52 min
Dec 19, 3:54 AM CSTTornado WarningJANAshley61 min
Dec 19, 3:55 AM CSTTornado WarningJANMorehouse15 min
Dec 19, 4:18 AM CSTTornado WarningSHVJackson, Lincoln42 min
Dec 19, 4:58 AM CSTSevere Thunderstorm WarningJANChicot32 min
Dec 19, 6:26 AM CSTTornado WarningSHVGrant64 min
Dec 19, 7:41 AM CSTTornado WarningJANCatahoula44 min
Dec 19, 8:13 AM CSTSevere Thunderstorm WarningJANTensas47 min
Dec 19, 8:24 AM CSTSevere Thunderstorm WarningJANConcordia46 min
Dec 19, 8:31 AM CSTSevere Thunderstorm WarningJANHumphreys, Sunflower24 min
Dec 19, 9:09 AM CSTSevere Thunderstorm WarningJANWarren46 min
Dec 19, 9:53 AM CSTSevere Thunderstorm WarningJANClaiborne, Copiah27 min

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 8.4 hours before the alert went out and 109 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 00:00Z on 2002-12-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1623 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2002-12-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 291 square meters per square second.1939587897117Sfc1 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
1623 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
618 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
291 m²/s²
0-3 km storm-relative helicity
354 m²/s²
Significant tornado parameter
3.8
Supercell composite
12.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 190843
SEL1  
SPC WW 190845
ARZ000-LAZ000-MSZ000-TXZ000-191600-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 791
STORM PREDICTION CENTER NORMAN OK
245 AM CST THU DEC 19 2002

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

   FAR SOUTHEAST ARKANSAS                           
   NORTHERN LOUISIANA                          
   WESTERN AND CENTRAL MISSISSIPPI                        
   FAR EAST-CENTRAL TEXAS                              

EFFECTIVE THIS THURSDAY MORNING FROM 245 AM UNTIL 1000 AM CST.

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 95 STATUTE MILES EAST AND WEST
OF A LINE FROM 25 MILES WEST OF FORT POLK LOUISIANA TO 25 MILES
EAST NORTHEAST OF GREENVILLE MISSISSIPPI.

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...THIS TORNADO WATCH REPLACES TORNADO WATCH
NUMBER 788.  WATCH NUMBER 788 WILL NOT BE IN EFFECT AFTER 245 AM
CST.  CONTINUE...WW 789...WW 790...

DISCUSSION...DESPITE LIMITED INSTABILITY ACROSS THE LOWER MS RIVER
VALLEY REGION...LARGE SCALE ASCENT WILL CONTINUE TO SUPPORT
THUNDERSTORMS INTO THE MID MORNING.  COMBINATION OF STRONG SHEAR
AND MID/UPPER LEVEL STORM RELATIVE WIND FIELDS...ACTIVITY WILL
CONTINUE IN THE FORM OF SMALL LINES/BOW ECHOES AND DISCRETE
SUPERCELLS.  

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 400. 
MEAN STORM MOTION VECTOR 23045.


...EVANS

310,0951 333,0921 333,0885 310,0920

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 18, 8:55 PM CSTTornado WatchSPCAshley, Bradley, Calhoun, Chicot, Cleveland, Columbia and 8 more6 hr
Dec 18, 9:05 PM CSTTornado WatchSPCCrittenden, Lee, Mississippi, Phillips, St. Francis6 hr
Dec 19, 12:30 AM CSTTornado WatchSPCAllen, Beauregard, Calcasieu, Evangeline7 hr
Dec 19, 6:30 AM CSTTornado WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Cameron and 26 more6 hr
Dec 19, 9:35 AM CSTTornado WatchSPCJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 2 more5 hr
Dec 19, 11:40 AM CSTTornado WatchSPCAscension, Assumption, Livingston, Orleans, Saint Bernard, Saint Charles and 7 more6 hr

Nearby

Tornado Watches in Louisiana, 2002Tornado Watches in Mississippi, 2002Tornado Watches in Texas, 2002Every tornado watch in 2002

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.