Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 114, NWS New Orleans, LA

September 6, 20214 parishes in Louisiana

NWS New Orleans, LA issued this flash flood warning at Sep 6, 2021, 1:54 PM CDT for 4 parishes in Louisiana. It was in force for 111 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 6, 2021, 1:54 PM CDT (18:54 UTC)
Expired
Sep 6, 2021, 3:45 PM CDT
In force
111 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Jefferson Parish, LA, Orleans Parish, LA, Plaquemines Parish, LA, Saint Bernard Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 6.9 hours before the alert went out and 54 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 2021-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2809 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2021-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.1939Sfc1 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
2809 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
623 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

657 
WGUS54 KLIX 061854
FFWLIX
LAC051-071-075-087-062045-
/O.NEW.KLIX.FF.W.0114.210906T1854Z-210906T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
Issued by National Weather Service Lake Charles LA
154 PM CDT Mon Sep 6 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  North Central Jefferson Parish in southeastern Louisiana...
  Southwestern Orleans Parish in southeastern Louisiana...
  Northwestern Plaquemines Parish in southeastern Louisiana...
  West Central St. Bernard Parish in southeastern Louisiana...

* Until 345 PM CDT.

* At 154 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. The expected rainfall rate is 1 to 3 inches in 1 
  hour. Additional rainfall amounts of 1 to 3 inches are possible in 
  the warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  New Orleans, Timberlane, Belle Chasse, Harvey, Marrero, Chalmette, 
  Avondale, Gretna, Harahan, Westwego, Jean Lafitte, Terrytown, 
  Woodmere, Estelle, Meraux, Poydras, Violet, Bridge City, Lafitte 
  and Waggaman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 2992 9006 2992 9003 2996 8990 2991 8983
      2985 8990 2984 8990 2974 9006 2974 9007
      2974 9011 2976 9013 2993 9022

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$
4 follow-up statements
361 
WGUS74 KLIX 061922
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
222 PM CDT Mon Sep 6 2021

LAC051-071-075-087-062045-
/O.CON.KLIX.FF.W.0114.000000T0000Z-210906T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson LA-Orleans LA-Plaquemines LA-St. Bernard LA-
222 PM CDT Mon Sep 6 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 PM CDT THIS 
AFTERNOON FOR NORTH CENTRAL JEFFERSON, SOUTHWESTERN ORLEANS, 
NORTHWESTERN PLAQUEMINES AND WEST CENTRAL ST. BERNARD PARISHES...

At 222 PM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1 and 3 inches of rain have 
fallen. The expected rainfall rate is 1 to 3 inches in 1 hour. 
Additional rainfall amounts of 1 to 3 inches are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  New Orleans, Belle Chasse, Timberlane, Harvey, Chalmette, Marrero, 
  Gretna, Westwego, Jean Lafitte, Terrytown, Woodmere, Estelle, 
  Meraux, Poydras, Violet and Bridge City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 2992 9006 2992 9003 2993 8999 2996 8990
      2991 8983 2985 8990 2984 8990 2974 9006
      2974 9007 2974 9008 2977 9011 2992 9016

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

MW
190 
WGUS74 KLIX 061929
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
229 PM CDT Mon Sep 6 2021

LAC051-071-075-087-062045-
/O.CON.KLIX.FF.W.0114.000000T0000Z-210906T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson LA-Orleans LA-Plaquemines LA-St. Bernard LA-
229 PM CDT Mon Sep 6 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 PM CDT THIS 
AFTERNOON FOR NORTH CENTRAL JEFFERSON, SOUTHWESTERN ORLEANS, 
NORTHWESTERN PLAQUEMINES AND WEST CENTRAL ST. BERNARD PARISHES...

At 229 PM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 3 inches of rain have 
fallen. The expected rainfall rate is 1 to 3 inches in 1 hour. 
Additional rainfall amounts of 1 to 3 inches are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  New Orleans, Belle Chasse, Timberlane, Harvey, Chalmette, Marrero, 
  Gretna, Jean Lafitte, Terrytown, Woodmere, Meraux, Poydras, Violet 
  and Estelle.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 2992 9012 2992 9006 2992 9003 2993 8999
      2993 8998 2996 8990 2991 8983 2985 8990
      2984 8990 2974 9006 2974 9007 2974 9008
      2978 9009

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

MW
216 
WGUS74 KLIX 061936
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
236 PM CDT Mon Sep 6 2021

LAC051-061946-
/O.CAN.KLIX.FF.W.0114.000000T0000Z-210906T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson LA-
236 PM CDT Mon Sep 6 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTH CENTRAL JEFFERSON 
PARISH...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

LAT...LON 2993 8999 2993 8998 2996 8990 2991 8983
      2985 8990 2984 8990 2985 8998 2985 9003
      2987 9002 2990 9001 2992 9003

$$

LAC071-075-087-062045-
/O.CON.KLIX.FF.W.0114.000000T0000Z-210906T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Orleans LA-Plaquemines LA-St. Bernard LA-
236 PM CDT Mon Sep 6 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 PM CDT THIS 
AFTERNOON FOR SOUTH CENTRAL ORLEANS, NORTHWESTERN PLAQUEMINES AND 
WEST CENTRAL ST. BERNARD PARISHES...

At 236 PM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 3 inches of rain have 
fallen. The expected rainfall rate is 1 to 3 inches in 1 hour. 
Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  New Orleans, Chalmette, Belle Chasse, Meraux, Violet, Poydras and 
  Terrytown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 2993 8999 2993 8998 2996 8990 2991 8983
      2985 8990 2984 8990 2985 8998 2985 9003
      2987 9002 2990 9001 2992 9003

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

CAB
034 
WGUS74 KLIX 062039
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
Issued by National Weather Service Lake Charles LA
339 PM CDT Mon Sep 6 2021

LAC071-075-087-062049-
/O.EXP.KLIX.FF.W.0114.000000T0000Z-210906T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Orleans LA-Plaquemines LA-St. Bernard LA-
339 PM CDT Mon Sep 6 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 345 PM CDT THIS AFTERNOON FOR 
SOUTH CENTRAL ORLEANS, NORTHWESTERN PLAQUEMINES AND WEST CENTRAL ST. 
BERNARD PARISHES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 2993 8999 2993 8998 2996 8990 2991 8983
      2985 8990 2984 8990 2985 8998 2985 9003
      2987 9002 2990 9001 2992 9003

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 4:00 AM CDTFlash Flood WatchLIXAssumption, East Baton Rouge, East Feliciana, Iberville, Orleans, Pointe Coupee and 9 more17 hr
Sep 6, 9:39 AM CDTSpecial Weather StatementLIXWashington36 min
Sep 6, 12:45 PM CDTSpecial Weather StatementLIXLafourche30 min
Sep 6, 12:47 PM CDTSpecial Weather StatementLIXSaint Charles28 min
Sep 6, 12:49 PM CDTSpecial Weather StatementLIXOrleans26 min
Sep 6, 1:05 PM CDTAreal Flood AdvisoryLIXLafourche, Saint Charles115 min
Sep 6, 1:17 PM CDTSpecial Weather StatementLIXOrleans, Saint Charles58 min
Sep 6, 1:24 PM CDTSpecial Marine WarningLIX66 min
Sep 6, 1:30 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines, Saint Charles81 min
Sep 6, 1:37 PM CDTSpecial Marine WarningLIX98 min

Nearby

Flash Flood Warnings in Louisiana, 2021Every flash flood warning in 2021

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.