Alert archive / Louisiana / Flash Flood Warnings in 1999

Flash Flood Warning 9, NWS New Orleans, LA

June 26, 1999Saint Bernard Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Jun 26, 1999, 4:08 PM CDT for Saint Bernard Parish, Louisiana. It was in force for 97 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: Jun 26, 1999, 4:08 PM CDT (21:08 UTC)
Expired: Jun 26, 1999, 5:45 PM CDT
In force: 97 min
Issued by: NWS New Orleans, LA
Area: Whole counties

County Saint Bernard Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 9.1 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.

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: 762 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 871 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 58 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KNEW 262111
FFWNEW
LAC051-075-087-089-262245-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
408 PM CDT SAT JUN 26 1999

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

* FLASH FLOOD WARNING FOR
   - SOUTHERN ST CHARLES PARISH IN SOUTHEASTERN LOUISIANA
   - CENTRAL AND SOUTHERN JEFFERSON PARISH IN SOUTHEASTERN LOUISIANA
   - ST BERNARD PARISH IN SOUTHEASTERN LOUISIANA
   - NORTHERN PLAQUEMINES PARISH IN SOUTHEASTERN LOUISIANA

* UNTIL 545 PM CDT

* AT 405 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  BAND OF STRONG THUNDERSTORMS FROM DES ALLEMANDES TO BELLE CHASSE
  TO VIOLET. THIS BAND WAS MOVING SOUTHEAST AT 10 MPH WITH
  INDIVIDUAL THUNDERSTORMS MOVING NORTHEAST AT 25 MPH.

 THE STRONGER THUNDERSTORMS HAVE A HISTORY OF PRODUCING RAINFALL
 RATES OF 2 TO 3 INCHES PER HOUR WHICH WILL FLOOD ROADS AND POORLY
 DRAINED AREAS QUICKLY. THE THREAT OF FLASH FLOODING WILL BE
 INCREASED BY STRONG THUNDERSTORMS REPEATEDLY TRACKING OVER THE
 SAME AREAS AS THE OVERALL AREA SLOWLY DRIFTS SOUTHEAST.

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 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, Jun 26, 10:15 AM CDT, 5 hours 53 minutes before

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-270100-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1015 AM CDT SAT JUN 26 1999

RICH TROPICAL MOISTURE REMAINS ACROSS THE REGION TODAY. WIDESPREAD
RAIN AND EMBEDDED THUNDERSTORMS WILL CONTINUE DUE TO AN UPPER AIR
DISTURBANCE MOVING SLOWLY EAST FROM TEXAS.

LOCALLY HEAVY RAIN WITH RAINFALL RATES OF 1 TO 3 INCHES PER HOUR CAN
BE EXPECTED WITH THE MORE INTENSE THUNDERSTORMS. OCCASIONAL
LIGHTNING AND GUSTY WINDS TO 30 MPH WILL ACCOMPANY THE STRONGER
THUNDERSTORMS. HOWEVER...SEVERE THUNDERSTORMS ARE NOT EXPECTED
TODAY. WATERSPOUTS MAY ALSO FORM OVER LARGE BODIES OF WATER.

Special weather statement, Jun 26, 11:20 AM CDT, 4 hours 48 minutes before

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-280100-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1120 AM CDT SAT JUN 26 1999

HIGH MOISTURE CONTENT IN THE ATMOSPHERE COMBINED WITH A WEAK TROUGH
ALOFT OVER LOUISIANA WILL HELP TO TRIGGER WIDELY SCATTERED AFTERNOON
SHOWERS AND THUNDERSTORMS.  BRIEF HEAVY RAIN...GUSTY WINDS TO 40 MPH
AND OCCASIONAL LIGHTNING MAY ACCOMPANY THE STRONGER THUNDERSTORMS.
NO SEVERE THUNDERSTORMS ARE EXPECTED THROUGH THIS EVENING.

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 26, 10:43 AM CDT	Flash Flood Warning	LIX	Saint Charles, Saint John the Baptist	117 min
Jun 26, 10:43 AM CDT	Flash Flood Warning	LIX	Saint James	117 min
Jun 26, 1:08 PM CDT	Flash Flood Warning	LIX	Ascension, Saint James, Saint John the Baptist	117 min
Jun 26, 2:58 PM CDT	Flash Flood Warning	LIX	Saint Charles	57 min
Jun 26, 4:08 PM CDT	Flash Flood Warning	LIX	Jefferson, Plaquemines, Saint Charles	97 min
Jun 26, 6:42 PM CDT	Flash Flood Warning	LIX	Jefferson, Lafourche	88 min
Jun 26, 6:42 PM CDT	Flash Flood Warning	LIX	Plaquemines	88 min

Nearby

Flash Flood Warnings in Louisiana, 1999 Every flash flood warning in 1999

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.