Alert archive / Louisiana / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 17, NWS Shreveport, LA

February 11, 2009Caldwell Parish, Jackson Parish, Ouachita Parish, Louisiana

NWS Shreveport, LA issued this severe thunderstorm warning at Feb 11, 2009, 3:49 AM CST for Caldwell Parish, Jackson Parish, Ouachita Parish, Louisiana. It was in force for 41 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Feb 11, 2009, 3:49 AM CST (09:49 UTC)
Expired
Feb 11, 2009, 4:30 AM CST
In force
41 min
Issued by
NWS Shreveport, LA
Area
Storm-based polygon

Counties Caldwell Parish, LA, Jackson Parish, LA, Ouachita Parish, LA

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Feb 11, 1:04 AM CSTTornado WatchSPC5 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 9.8 hours before the alert went out and 140 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 2009-02-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 367 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 00:00Z on 2009-02-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 410 square meters per square second.1939587897117136Sfc1 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
367 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
785 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
410 m²/s²
0-3 km storm-relative helicity
547 m²/s²
Significant tornado parameter
0.7
Supercell composite
10.5

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Shreveport, LA wrote its last area forecast discussion before this severe thunderstorm warning went out at Feb 11, 3:11 AM CST, 38 minutes earlier.

Area forecast discussion, Feb 11, 3:11 AM CST, 38 minutes before
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Hazardous weather outlook, Feb 10, 12:00 PM CST, 15 hours 49 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
1200 PM CST TUE FEB 10 2009

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-111200-
ANGELINA-BIENVILLE-BOSSIER-BOWIE-CADDO-CALDWELL-CAMP-CASS-CHEROKEE-
CLAIBORNE-COLUMBIA-DE SOTO-FRANKLIN-GRANT-GREGG-HARRISON-HEMPSTEAD-
HOWARD-JACKSON-LA SALLE-LAFAYETTE-LINCOLN-LITTLE RIVER-MARION-
MCCURTAIN-MILLER-MORRIS-NACOGDOCHES-NATCHITOCHES-NEVADA-OUACHITA-
PANOLA-RED RIVER LA-RED RIVER TX-RUSK-SABINE LA-SABINE TX-
SAN AUGUSTINE-SEVIER-SHELBY-SMITH-TITUS-UNION AR-UNION LA-UPSHUR-
WEBSTER-WINN-WOOD-
1200 PM CST TUE FEB 10 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST OKLAHOMA...
SOUTHWEST ARKANSAS...NORTHEAST TEXAS AND FOR NORTHWEST AND NORTH
CENTRAL LOUISIANA.

.DAY ONE...TODAY AND TONIGHT...

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM LATE THIS
AFTERNOON THROUGH TONIGHT...GENERALLY NORTH OF A LINE FROM TYLER...
TEXAS...TO SHREVEPORT...LOUISIANA...TO EL DORADO...ARKANSAS.  A
SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS ACROSS THE REMAINDER OF
THE FOUR STATE REGION.

THE MAIN SEVERE WEATHER RISKS WILL BE TORNADOES AND DAMAGING WINDS
IN EXCESS OF 60 MILES AN HOUR.  A FEW SEVERE STORMS MAY PRODUCE
LARGE HAIL THIS AFTERNOON ACROSS NORTHEAST TEXAS AND SOUTHEAST
OKLAHOMA.

A STRONG STORM SYSTEM IS POISED TO AFFECT THE FOUR STATE REGION
THROUGH TONIGHT.  WITH THE COMBINATION OF LOW LEVEL WIND SHEAR...
JET STREAM DYNAMICS...AND INSTABILITY...THUNDERSTORMS WILL LIKELY
BECOME SEVERE.

ISOLATED SUPERCELL THUNDERSTORMS WILL LIKELY DEVELOP LATE THIS
AFTERNOON TO THE WEST OF A MINEOLA TEXAS TO IDABEL OKLAHOMA
LINE.  THESE SUPERCELL THUNDERSTORMS...WHICH WILL POSE THE GREATEST
RISK OF TORNADO DEVELOPMENT...COULD AFFECT NORTHEAST TEXAS EARLY
THIS EVENING.  AS THE EVENING PROGRESSES...THE THUNDERSTORMS SHOULD
DEVELOP INTO A SQUALL LINE ACROSS EAST TEXAS AND SOUTHEAST
OKLAHOMA.  THE SQUALL LINE WILL LIKELY MOVE INTO SOUTHWEST ARKANSAS
AND NORTHWEST LOUISIANA AROUND MIDNIGHT...PROBABLY REACHING EL
DORADO...MONROE...AND JENA BETWEEN 2 AND 4 AM.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY...

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

STORM SPOTTER GROUP...HAM RADIO OPERATOR...AND EMERGENCY MANAGEMENT
PERSONNEL ACTIVATION WILL LIKELY BE NEEDED BY LATE THIS AFTERNOON
ACROSS EAST TEXAS AND SOUTHEAST OKLAHOMA.  ACTIVATION WILL LIKELY BE
REQUIRED ACROSS THE REMAINDER OF THE FOUR STATE REGION TONIGHT.

44

In the hours before

Local storm report, Feb 11, 1:58 AM CST, 1 hour 51 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SHREVEPORT LA
158 AM CST WED FEB 11 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1200 AM     TSTM WND DMG     HENDERSON               32.16N 94.80W
02/11/2009                   RUSK               TX   BROADCAST MEDIA

            NUMEROUS TREES DOWNED IN THE CITY OF HENDERSON

1225 AM     TSTM WND DMG     NACOGDOCHES             31.61N 94.65W
02/11/2009                   NACOGDOCHES        TX   LAW ENFORCEMENT

            NUMEROUS TREES DOWNED ACROSS THE COUNTY

1225 AM     TSTM WND DMG     BECKVILLE               32.24N 94.46W
02/11/2009                   PANOLA             TX   LAW ENFORCEMENT

            TREES DOWNED ON FM 1794 AND CR 266

1225 AM     TSTM WND DMG     NACOGDOCHES             31.61N 94.65W
02/11/2009                   NACOGDOCHES        TX   LAW ENFORCEMENT

            TREE DOWNED ON TRUCK

1225 AM     HAIL             NACOGDOCHES             31.61N 94.65W
02/11/2009  E1.00 INCH       NACOGDOCHES        TX   LAW ENFORCEMENT

1227 AM     TSTM WND DMG     12 S MARSHALL           32.36N 94.35W
02/11/2009                   HARRISON           TX   LAW ENFORCEMENT

            TREE DOWN ON US HWY 59 S JUST NORTH OF THE PANOLA COUNTY
            LINE

1241 AM     HAIL             CARTHAGE                32.15N 94.34W
02/11/2009  E0.75 INCH       PANOLA             TX   BROADCAST MEDIA

0110 AM     TSTM WND DMG     SHREVEPORT              32.47N 93.80W
02/11/2009                   CADDO              LA   LAW ENFORCEMENT

            NUMEROUS DOWNED TREES ACROSS THE CITY OF SHREVEPORT

0116 AM     TSTM WND GST     SHREVEPORT              32.47N 93.80W
02/11/2009  M60.00 MPH       CADDO              LA   ASOS

            MEASURED AT KDTN

0130 AM     TSTM WND GST     BOSSIER CITY            32.52N 93.66W
02/11/2009  M59.00 MPH       BOSSIER            LA   ASOS

            MEASURED AT KBAD

&&

12
Local storm report, Feb 11, 2:03 AM CST, 1 hour 46 minutes before
PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE SHREVEPORT LA
203 AM CST WED FEB 11 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0120 AM     TSTM WND GST     BOSSIER CITY            32.52N 93.66W
02/11/2009  M59.00 MPH       BOSSIER            LA   ASOS

            MEASURED AT KBAD - CORRECTION TO TIME OF OCCURRANCE

&&

12
Local storm report, Feb 11, 2:48 AM CST, 1 hour 1 minute before
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Local storm report, Feb 11, 3:19 AM CST, 30 minutes before
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Local storm report, Feb 11, 3:28 AM CST, 21 minutes before
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Local storm report, Feb 11, 3:49 AM CST, 0 minutes before
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The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 10, 10:58 PM CSTSevere Thunderstorm WarningSHVCherokee, Smith62 min
Feb 10, 11:04 PM CSTSevere Thunderstorm WarningSHVCamp, Franklin, Red River, Titus, Upshur, Wood41 min
Feb 10, 11:49 PM CSTSevere Thunderstorm WarningSHVAngelina, Cherokee, Gregg, Harrison, Nacogdoches, Panola and 4 more56 min
Feb 11, 12:40 AM CSTSevere Thunderstorm WarningSHVHarrison, Marion, Nacogdoches, Panola, Rusk, Shelby65 min
Feb 11, 12:42 AM CSTSevere Thunderstorm WarningSHVAngelina, Nacogdoches, San Augustine48 min
Feb 11, 1:26 AM CSTSevere Thunderstorm WarningSHVAngelina, Sabine, San Augustine, Shelby49 min
Feb 11, 2:14 AM CSTSevere Thunderstorm WarningSHVSabine46 min
Feb 11, 10:55 AM CSTLake Wind AdvisorySHVAngelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more5 hr
Feb 11, 1:34 AM CSTSevere Thunderstorm WarningSHVBienville, Claiborne, De Soto, Lincoln, Natchitoches, Red River and 1 more41 min
Feb 11, 2:10 AM CSTSevere Thunderstorm WarningSHVBienville, Claiborne, Lincoln, Union50 min
Feb 11, 2:53 AM CSTSevere Thunderstorm WarningSHVJackson, Lincoln, Ouachita, Union52 min
Feb 11, 2:59 AM CSTSevere Thunderstorm WarningSHVGrant, Natchitoches, Winn61 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2009Every severe thunderstorm warning in 2009

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.