Alert archive / Louisiana / Flash Flood Warnings in 1998
Flash Flood Warning 27, NWS New Orleans, LA
NWS New Orleans, LA issued this flash flood warning at Sep 11, 1998, 12:51 PM CDT for Saint Tammany Parish, Louisiana. It was in force for 3 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, 12:51 PM CDT (17:51 UTC)
- Expired
- Sep 11, 1998, 3:45 PM CDT
- In force
- 3 hr
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
County Saint Tammany Parish, LA
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 5.9 hours before the alert went out and 30 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 111751 FFWNEW LAC051-071-075-087-103-112045- BULLETIN - IMMEDIATE BROADCAST REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE NEW ORLEANS LA 1251 PM 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 - ST BERNARD PARISH IN SOUTHEASTERN LOUISIANA - PLAQUEMINES PARISH IN SOUTHEASTERN LOUISIANA * UNTIL 345 PM CDT *AT 1245 PM CDT...VERY SERIOUS...DANGEROUS FLOODING WAS ONGOING ACROSS MUCH OF METROPOLITAN NEW ORLEANS AND ADDITIONAL HEAVY RAIN CONTINUED TO DEVELOP AND MOVE ACROSS THE AREA. DOPPLER RADAR CONTINUED TO INDICATE RAIN FALING AT THE RATE OF 2 TO 3 INCHES PER HOUR FROM NORTHERN PLAQUEIMINES PARISH ACROSS UPPER JEFFERSON... ORLEANS...AND ST BERNARD PARISH ACROSS LAKE PONTCHARTRAIN INTO WESTERN ST TAMMANY PARISH. MANY AREAS HAVE RECEIVED CLOSE TO 10 INCHES OF RAIN OR MORE IN THE LAST 24 HOURS. INTERSTATE 10 IS CLOSED TO DUE HIGH WATER FROM NEW ORLEANS TO THE JEFFERSON PARISH LINE AND MANY STREETS ARE IMPASSIBLE. MOTORISTS ARE URGED TO STAY OFF THE ROADS AND PERSONS SHOULD STAY INDOORS UNTIL WELL AFTER THE HEAVY RAIN ENDS. STAY AWAY FROM DRAINAGE CANALS AND HIGH WATER AREAS. 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 SAFE"LY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHER 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
Special weather statement, Sep 11, 11:00 AM CDT, 1 hour 51 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 51 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, 12:07 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, 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.