Alert archive / Louisiana / Tornado Watches in 2003

Tornado Watch 366

May 13, 200317 parishes in Louisiana

The Storm Prediction Center issued this tornado watch at May 13, 2003, 10:45 PM CDT for 17 parishes in Louisiana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 13, 2003, 10:45 PM CDT (03:45 UTC)
Expired
May 14, 2003, 4:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Sabine Parish, LA, Union Parish, LA, Webster Parish, LA, Winn Parish, LA

The radar

The Shreveport radar (KSHV), 68 km from the middle of the area, began a volume at 03:45 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

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

IssuedProductOfficeCountiesLasted
May 13, 11:08 PM CDTTornado WarningSHVBossier, Caddo52 min
May 13, 11:08 PM CDTTornado WarningSHVBienville67 min
May 13, 11:11 PM CDTSevere Thunderstorm WarningSHVJackson64 min
May 13, 11:19 PM CDTTornado WarningSHVJackson56 min
May 13, 11:28 PM CDTSevere Thunderstorm WarningSHVWebster62 min
May 13, 11:48 PM CDTSevere Thunderstorm WarningSHVBienville57 min
May 14, 12:00 AM CDTTornado WarningSHVCaddo, De Soto, Red River60 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 00:00Z, 3.8 hours before the alert went out and 61 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 2003-05-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2326 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 00:00Z on 2003-05-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 142 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
2326 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
1006 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
142 m²/s²
0-3 km storm-relative helicity
401 m²/s²
Significant tornado parameter
3.2
Supercell composite
18.5

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 140340
SEL6  
SPC WW 140345
LAZ000-140900-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 366 
NWS STORM PREDICTION CENTER NORMAN OK 
1045 PM CDT TUE MAY 13 2003

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

       NORTHERN LOUISIANA

EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 1045 PM
UNTIL 400 AM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 55 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 20 MILES SOUTH SOUTHWEST OF SHREVEPORT
LOUISIANA TO 25 MILES SOUTH SOUTHEAST OF MONROE LOUISIANA.

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 SEVERE
THUNDERSTORM WATCH NUMBER 364. WATCH NUMBER 364 WILL NOT BE IN
EFFECT AFTER 1045 PM CDT. CONTINUE...WW 365...


DISCUSSION...SEVERAL STRONG SUPERCELLS CONTINUE TO DEVELOP SEWD
ACROSS NWRN LA.  WITH IMPRESSIVE VEERING SHEAR PROFILE COUPLED WITH
THE STRONG INSTABILITY...ISOLATED TORNADOES ARE LIKELY ALONG WITH
THE VERY LARGE HAIL AND DAMAGING WINDS

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600.
MEAN STORM MOTION VECTOR 32030.


...HALES

325,0935 325,0915 312,0915 312,0935

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 13, 8:05 PM CDTMesoscale DiscussionSPCBienville, Bossier, Caddo, Claiborne, De Soto, Lincoln and 2 more55 min
May 13, 8:30 PM CDTSevere Thunderstorm WatchSPCBienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 15 more5 hr
May 14, 10:55 AM CDTMesoscale DiscussionSPCBienville, Bossier, Caddo, Claiborne, Webster2 hr
May 14, 2:30 PM CDTTornado WatchSPCBossier, Caddo, Claiborne, Lincoln, Ouachita, Union and 1 more6 hr
May 14, 5:17 PM CDTMesoscale DiscussionSPCBossier, Claiborne, Jackson, Lincoln, Union, Webster118 min
May 14, 6:10 PM CDTSevere Thunderstorm WatchSPCBienville, Bossier, Caddo, Caldwell, Claiborne, East Carroll and 13 more6 hr

Nearby

Tornado Watches in Louisiana, 2003Every 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; radar from the NEXRAD Level II archive.