Alert archive / Louisiana / Tornado Warnings in 1998

Tornado Warning 23, NWS New Orleans, LA

September 11, 1998Orleans Parish, Saint Bernard Parish, Louisiana

NWS New Orleans, LA issued this tornado warning at Sep 11, 1998, 2:14 PM CDT for Orleans Parish, Saint Bernard Parish, Louisiana. It was in force for 36 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, 2:14 PM CDT (19:14 UTC)
Expired
Sep 11, 1998, 2:50 PM CDT
In force
36 min
Issued by
NWS New Orleans, LA
Area
Whole counties

Counties Orleans Parish, LA, Saint Bernard Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 7.2 hours before the alert went out and 35 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, Slidell Radar S, LA at 12:00Z on 1998-09-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 173 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, Slidell Radar S, LA at 12:00Z on 1998-09-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 220 square meters per square second.193958Sfc1 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
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

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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

Special weather statement, Sep 11, 11:00 AM CDT, 3 hours 14 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, 3 hours 14 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.

IssuedProductOfficeCountiesLasted
Sep 10, 7:06 PM CDTTornado WarningLIXJefferson29 min
Sep 10, 8:41 PM CDTTornado WarningLIXSaint Charles34 min
Sep 11, 10:02 AM CDTSevere Thunderstorm WarningLIXOrleans, Saint Tammany43 min
Sep 11, 10:50 AM CDTFlash Flood WarningLIXJefferson, Orleans, Plaquemines, Saint Bernard, Saint Tammany2 hr
Sep 11, 12:07 PM CDTTornado WarningLIXPlaquemines33 min
Sep 11, 12:51 PM CDTFlash Flood WarningLIXJefferson, Orleans, Plaquemines, Saint Bernard3 hr
Sep 11, 12:51 PM CDTFlash Flood WarningLIXSaint Tammany3 hr
Sep 11, 2:14 PM CDTTornado WarningLIXOrleans, Saint Bernard41 min
Sep 11, 5:15 PM CDTFlash Flood WarningLIXPlaquemines, Saint Bernard3 hr
Sep 11, 5:34 PM CDTFlash Flood WarningLIXJefferson, Orleans3 hr

Nearby

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