Alert archive / Louisiana / Flash Flood Warnings in 1998
Flash Flood Warning 25, NWS New Orleans, LA
NWS New Orleans, LA issued this flash flood warning at Sep 11, 1998, 10:50 AM CDT for 5 parishes in Louisiana. It was in force for 2 hr. 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, 10:50 AM CDT (15:50 UTC)
- Expired
- Sep 11, 1998, 1:00 PM CDT
- In force
- 2 hr
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
Counties Jefferson Parish, LA, Orleans Parish, LA, Plaquemines Parish, LA, Saint Bernard Parish, LA, Saint Tammany Parish, LA
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 3.8 hours before the alert went out and 43 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.
- 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
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KNEW 111550 FFWNEW LAC051-071-075-087-103-111800- BULLETIN - IMMEDIATE BROADCAST REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE NEW ORLEANS LA 1050 AM CDT FRI SEP 11 1998 THE NATIONAL WEATHER SERVICE IN NEW ORLEANS LA HAS ISSUED A... * FLASH FLOOD WARNING FOR - ST TAMMANY PARISH IN SOUTHEASTERN LOUISIANA - JEFFERSON PARISH IN SOUTHEASTERN LOUISIANA - ORLEANS PARISH IN SOUTHEASTERN LOUISIANA - NORTHERN ST BERNARD PARISH IN SOUTHEASTERN LOUISIANA - PLAQUEMINES PARISH IN SOUTHEASTERN LOUISIANA * UNTIL 100 PM CDT *AT 1040 AM CDT...BANDS OF VERY HEAVY RAIN ASSOCIATED WITH TROPICAL SHOWERS AND THUNDERSTORMS WERE MOVING ACROSS MUCH OF THE NEW ORLEANS METROPOLITAN AREA AND AREAS TO THE NORTH AND SOUTH FROM NEAR GRANDE ISLE NORTH ACROSS JEFFERSON...PLAQUEMINES... WESTERN ORLEANS PARISHES...AND CONTINUING NORTH ACROSS LAKE PONTCHARTRAIN INTO WESTERN AND CENTRAL ST TAMMANY PARISH. RAINFALL RATES OF 2 TO 3 INCHES PER HOUR WERE INDICATED BY DOPPLER RADAR IN THE HEAVIEST RAINBANDS...AND HEAVY RAIN MAY PERSIST IN SOME AREAS UP TO 2 HOURS PRODUCING UP TO 6 INCHES OF ADDITIONAL RAIN THROUGH 1 PM. THIS IS IN ADDITION TO THE 4 TO 8 INCHES THAT HAS ALREADY FALLEN ON MUCH OF SOUTH SHORE OF LAKE PONTCHARTRAIN. DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHE8R GROUND.
What forecasters said that day
The local office's own words before this flash flood 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, 4 hours 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
TREESLocal storm report, Sep 11, 6:50 AM CDT, 4 hours 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
TREESThe 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, 12:07 PM CDT | Tornado Warning | LIX | Plaquemines | 33 min |
| 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
Flash Flood Warnings in Louisiana, 1998Every flash flood warning 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.