Alert archive / Louisiana / Tornado Warnings in 1998

Tornado Warning 22, NWS New Orleans, LA

September 11, 1998Plaquemines Parish, Louisiana

NWS New Orleans, LA issued this tornado warning at Sep 11, 1998, 12:07 PM CDT for Plaquemines Parish, Louisiana. It was in force for 33 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: Sep 11, 1998, 12:07 PM CDT (17:07 UTC)
Expired: Sep 11, 1998, 12:40 PM CDT
In force: 33 min
Issued by: NWS New Orleans, LA
Area: Whole counties

County Plaquemines Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 5.1 hours before the alert went out and 79 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: 173 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 653 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 220 m²/s²
0-3 km storm-relative helicity: 353 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KNEW 111707 RRA
TORNEW
LAC075-111740-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1207 PM CDT FRI SEP 11 1998

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS LA HAS ISSUED A...

* TORNADO WARNING FOR
   - NORTHERN PLAQUEMINES PARISH IN SOUTHEASTERN LOUISIANA

* UNTIL 1240 PM CDT

* AT 1203 PM CDT... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  PRODUCING A POSSIBLE TORNADO IN NORTHERN PLAQUEMINES PARISH ABOUT
  10 MILES SOUTH OF BELLE CHASSE.

* THE STORM IS MOVING TO THE NORTH AT 25 MPH AND WILL AFFECT
  AREAS AROUND BELLE CHASSE...BELAIR AND BERTRANDVILLE.

IF YOU ARE IN THESE AREAS...SEEK SHELTER IN A SMALL INTERIOR ROOM
AWAY FROM WINDOWS

IF YOU ARE IN THE PATH OF A TORNADO...GET UNDER A WORKBENCH OR PIECE
OF STURDY FURNITURE. SEEK SHELTER IN AN INTERIOR ROOM SUCH AS A
CLOSET ON THE LOWEST FLOOR.  USE BLANKETS...PILLOWS...OR CUSHIONS TO
COVER YOUR BODY.  AVOID WINDOWS.

What forecasters said that day

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

In the hours before

Local storm report, Sep 11, 6:50 AM CDT, 5 hours 17 minutes before

PRELIMINARY LOCAL STORM REPORT...CORRECTION
NATIONAL WEATHER SERVICE OFFICE NEW ORLEANS LOUISIANA
650 AM CDT THU SEP 11 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....PARISH LOCATION....

0535 PM    MONTEGUT                  LA   TORNADO
09/10/98   TERREBONNE                     TREES KNOCKED DOWN.

0540 PM    CUT OFF                   LA   WIND DAMAGE
09/10/98   LAFOURCHE                      DAMAGE TO TREES AND SLIGHT
                                          DAMAGE TO AMERICAN LEGION
                                          HOME.

0620 PM    GALLIANO                  LA   TORNADO
09/10/98   LAFOURCHE                      HEAVY RAINFALL. ONE HOUSE
                                          DESTROYED AND NINE OTHER
                                          HOUSES WERE AFFECTED.

0815 PM    DES ALLEMANDS             LA   FLOODING
09/10/98   ST CHARLES                     COUPLE OF HOUSES WERE
 l                                         FLOODED.

0900 PM    DES ALLEMANDS             LA   WIND DAMAGE
09/10/98   ST CHARLES                     GUSTY WINDS DOWNED SEVERAL
                                          TREES

Local storm report, Sep 11, 6:50 AM CDT, 5 hours 17 minutes before

PRELIMINARY LOCAL STORM REPORT...CORRECTION
NATIONAL WEATHER SERVICE OFFICE NEW ORLEANS LOUISIANA
650 AM CDT THU SEP 11 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....PARISH LOCATION....

0535 PM    MONTEGUT                  LA   TORNADO
09/10/98   TERREBONNE                     TREES KNOCKED DOWN.

0540 PM    CUT OFF                   LA   WIND DAMAGE
09/10/98   LAFOURCHE                      DAMAGE TO TREES AND SLIGHT
                                          DAMAGE TO AMERICAN LEGION
                                          HOME.

0620 PM    GALLIANO                  LA   TORNADO
09/10/98   LAFOURCHE                      HEAVY RAINFALL. ONE HOUSE
                                          DESTROYED AND NINE OTHER
                                          HOUSES WERE AFFECTED.

0815 PM    DES ALLEMANDS             LA   FLOODING
09/10/98   ST CHARLES                     COUPLE OF HOUSES WERE
 l                                         FLOODED.

0900 PM    DES ALLEMANDS             LA   WIND DAMAGE
09/10/98   ST CHARLES                     GUSTY WINDS DOWNED SEVERAL
                                          TREES

Special weather statement, Sep 11, 11:00 AM CDT, 1 hour 7 minutes before

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-112300-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1100 AM CDT FRI SEP 11 1998

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR ALL OF SOUTHEAST
LOUISIANA...EXTREME SOUTH AND SOUTHWEST MISSISSIPPI AND COASTAL
MISSISSIPPI.

BANDS OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH TROPICAL
STORM FRANCES WILL AFFECT SOUTHEAST LOUISIANA THIS AFTERNOON AND
TONIGHT. GUSTY EAST WINDS UP TO 30 MILES AN HOUR IN BANDS OF SHOWERS
AND THUNDERSTORM AND VERY HEAVY RAINFALL WILL BE THE MAIN THREAT.
IN ADDITION...THE WIND PROFILE FROM THE SURFACE TO THE MIDDLE
LAYERS OF THE ATMOSPHERE MAY PRODUCE SHORT LIVED ISOLATED WATERSPOUTS
AND TORNADOEnS IN THE SLIGHT RISK AREA THIS AFTERNOON AND TONIGHT.

Special weather statement, Sep 11, 11:00 AM CDT, 1 hour 7 minutes before

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-112300-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1100 AM CDT FRI SEP 11 1998

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR ALL OF SOUTHEAST
LOUISIANA...EXTREME SOUTH AND SOUTHWEST MISSISSIPPI AND COASTAL
MISSISSIPPI.

BANDS OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH TROPICAL
STORM FRANCES WILL AFFECT SOUTHEAST LOUISIANA THIS AFTERNOON AND
TONIGHT. GUSTY EAST WINDS UP TO 30 MILES AN HOUR IN BANDS OF SHOWERS
AND THUNDERSTORM AND VERY HEAVY RAINFALL WILL BE THE MAIN THREAT.
IN ADDITION...THE WIND PROFILE FROM THE SURFACE TO THE MIDDLE
LAYERS OF THE ATMOSPHERE MAY PRODUCE SHORT LIVED ISOLATED WATERSPOUTS
AND TORNADOEnS IN THE SLIGHT RISK AREA THIS AFTERNOON AND TONIGHT.

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 10, 7:06 PM CDT	Tornado Warning	LIX	Jefferson	29 min
Sep 10, 8:41 PM CDT	Tornado Warning	LIX	Saint Charles	34 min
Sep 11, 10:02 AM CDT	Severe Thunderstorm Warning	LIX	Orleans, Saint Tammany	43 min
Sep 11, 10:50 AM CDT	Flash Flood Warning	LIX	Jefferson, Orleans, Plaquemines, Saint Bernard, Saint Tammany	2 hr
Sep 11, 12:51 PM CDT	Flash Flood Warning	LIX	Jefferson, Orleans, Plaquemines, Saint Bernard	3 hr
Sep 11, 12:51 PM CDT	Flash Flood Warning	LIX	Saint Tammany	3 hr
Sep 11, 2:14 PM CDT	Tornado Warning	LIX	Orleans, Saint Bernard	36 min
Sep 11, 2:14 PM CDT	Tornado Warning	LIX	Orleans, Saint Bernard	41 min
Sep 11, 5:15 PM CDT	Flash Flood Warning	LIX	Plaquemines, Saint Bernard	3 hr
Sep 11, 5:34 PM CDT	Flash Flood Warning	LIX	Jefferson, Orleans	3 hr

Nearby

Tornado Warnings in Louisiana, 1998 Every tornado warning in 1998 Tornadoes in 1998

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.