Alert archive / Louisiana / Tornado Watches in 2003

Tornado Watch 52

March 18, 2003Ashley County, Chicot County, Union County, Arkansas; 34 parishes in Louisiana; Adams County, Washington County, Wilkinson County, Mississippi

The Storm Prediction Center issued this tornado watch at Mar 18, 2003, 2:15 PM CST for Ashley County, Chicot County, Union County, Arkansas; 34 parishes in Louisiana; Adams County, Washington County, Wilkinson County, Mississippi. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Mar 18, 2003, 2:15 PM CST (20:15 UTC)
Expired: Mar 18, 2003, 9:00 PM CST
In force: 7 hr
Issued by: the Storm Prediction Center

All 40 counties

Ashley County, AR, Chicot County, AR, Union County, AR, Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia 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, Pointe Coupee Parish, LA, Rapides Parish, LA, Richland Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Washington County, MS, Wilkinson County, MS

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Mar 18, 3:08 PM CST	Severe Thunderstorm Warning	LCH	Vernon	67 min
Mar 18, 3:42 PM CST	Severe Thunderstorm Warning	LCH	Rapides	63 min
Mar 18, 4:45 PM CST	Tornado Warning	LCH	Avoyelles, Rapides	45 min
Mar 18, 5:08 PM CST	Tornado Warning	JAN	Catahoula	62 min
Mar 18, 5:15 PM CST	Tornado Warning	SHV	LaSalle	30 min
Mar 18, 5:36 PM CST	Tornado Warning	JAN	Concordia	59 min
Mar 18, 6:00 PM CST	Severe Thunderstorm Warning	JAN	Franklin	60 min
Mar 18, 6:02 PM CST	Severe Thunderstorm Warning	JAN	Franklin	58 min
Mar 18, 6:09 PM CST	Severe Thunderstorm Warning	JAN	Franklin	51 min
Mar 18, 6:12 PM CST	Tornado Warning	JAN	Adams, Jefferson	58 min
Mar 18, 6:14 PM CST	Tornado Warning	JAN	Tensas	61 min
Mar 18, 6:21 PM CST	Tornado Warning	JAN	Franklin	44 min
Mar 18, 6:40 PM CST	Severe Thunderstorm Warning	JAN	Concordia	30 min
Mar 18, 6:46 PM CST	Tornado Warning	JAN	Madison	59 min
Mar 18, 7:07 PM CST	Severe Thunderstorm Warning	JAN	Adams	48 min
Mar 18, 7:12 PM CST	Severe Thunderstorm Warning	LIX	West Feliciana	48 min
Mar 18, 7:28 PM CST	Severe Thunderstorm Warning	JAN	Tensas	42 min
Mar 18, 7:55 PM CST	Severe Thunderstorm Warning	JAN	East Carroll	45 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 8.3 hours before the alert went out and 150 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 787 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 129 m²/s²
0-3 km storm-relative helicity: 147 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 182016
SEL2
SPC WW 182015
ARZ000-LAZ000-190300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 52
STORM PREDICTION CENTER NORMAN OK
215 PM CST TUE MAR 18 2003

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

   SOUTH CENTRAL AND SOUTHEAST ARKANSAS                           
   MUCH OF LOUISIANA                          

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 215 PM UNTIL 900
PM CST.

 ...THIS IS A PARTICULARLY DANGEROUS SITUATION...
 
DAMAGING TORNADOES...LARGE 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 65 STATUTE MILES EAST AND WEST
OF A LINE FROM 35 MILES WEST SOUTHWEST OF LAFAYETTE LOUISIANA TO 45
MILES EAST 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...THIS TORNADO WATCH REPLACES TORNADO WATCH
NUMBER 51.  WATCH NUMBER 51 WILL NOT BE IN EFFECT AFTER 215 PM CST.

DISCUSSION...STORMS ARE RAPIDLY CHANGING CHARACTER AS EXIT REGION
OF STRONG MID LEVEL JET NOW TURNS NEWD INTO SERN TX.  AIR MASS IN
THE WARM SECTOR ACROSS SRN LA IS MODERATELY UNSTABLE WITH CAPE TO
1300 J/KG.  SEVERAL BOUNDARIES ARE ALSO ACROSS NERN AND CENTRAL LA. 
AS LINE OF SEVERE STORMS MOVE EWD...INTERACTION WITH THESE
BOUNDARIES MAY ENHANCE TORNADO POTENTIAL WHERE DEEP LAYER SHEAR IS
55 TO 70 KTS.


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 22035.


...MCCARTHY

332,0905 300,0912 300,0933 332,0931

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 18, 9:36 AM CST	Mesoscale Discussion	SPC	Hempstead, Howard, Lafayette, Little River, Miller, Pike and 1 more	3 hr
Mar 18, 11:40 AM CST	Tornado Watch	SPC	Allen, Beauregard, Calcasieu, Cameron, Grant, Natchitoches and 2 more	5 hr
Mar 18, 1:12 PM CST	Mesoscale Discussion	SPC	Bienville, Caldwell, Catahoula, De Soto, Franklin, Grant and 13 more	2 hr
Mar 18, 3:33 PM CST	Mesoscale Discussion	SPC	Bienville, Caldwell, Catahoula, De Soto, Franklin, Grant and 13 more	57 min
Mar 18, 4:30 PM CST	Mesoscale Discussion	SPC	Ascension, East Baton Rouge, East Carroll, East Feliciana, Livingston, Madison and 8 more	2 hr
Mar 18, 5:05 PM CST	Tornado Watch	SPC	Ascension, East Baton Rouge, East Feliciana, Iberville, Livingston, Saint Helena and 4 more	6 hr

Nearby

Tornado Watches in Louisiana, 2003 Tornado Watches in Arkansas, 2003 Tornado Watches in Mississippi, 2003 Every tornado watch in 2003

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.