Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 7, NWS New Orleans, LA

April 8, 2021Jefferson Parish, Orleans Parish, Saint Charles Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Apr 8, 2021, 3:42 AM CDT for Jefferson Parish, Orleans Parish, Saint Charles Parish, Louisiana. It was in force for 5 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 8, 2021, 3:42 AM CDT (08:42 UTC)
Expired
Apr 8, 2021, 8:45 AM CDT
In force
5 hr
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Jefferson Parish, LA, Orleans Parish, LA, Saint Charles Parish, LA

What was reported inside it

TimeReportWhereRemark
Apr 8, 4:12 AM CDTFLASH FLOOD1 N Kenner, LAKENNER EMERGENCY MANAGEMENT RELAYED A REPORT FROM POLICE THAT THE INTERSECTION OF CHATEAU AND VINTAGE WAS IMPASSABLE BY AN SUV.
Apr 8, 4:32 AM CDTFLASH FLOOD5 Nnw Avondale, LASOUTHEAST SEARCH AND RESCUE REPORTED WATER OVER 2 FEET DEEP ON SOFIA STREET IN RIVER RIDGE.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 8.7 hours before the alert went out and 52 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 00:00Z on 2021-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1186 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2021-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 147 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
1186 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
722 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
147 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.9
Supercell composite
5.8

Open this sounding in Storm Lab

The text

As transmitted.

251 
WGUS54 KLIX 080842
FFWLIX
LAC051-071-089-081145-
/O.NEW.KLIX.FF.W.0007.210408T0842Z-210408T1145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
342 AM CDT Thu Apr 8 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  Northwestern Jefferson Parish in southeastern Louisiana...
  Southwestern Orleans Parish in southeastern Louisiana...
  Northwestern St. Charles Parish in southeastern Louisiana...

* Until 645 AM CDT.

* At 342 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  New Orleans, Metairie, Avondale, Marrero, Harvey, Hahnville, 
  Chalmette, Laplace, East New Orleans, Jefferson, Gretna, Harahan, 
  Westwego, River Ridge, Elmwood, Waggaman, Bridge City, Ama, St. 
  Rose and Destrehan.

Additional rainfall amounts of 2 to 4 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3004 9042 2998 9030 2999 9028 3005 9028
      3002 9013 3004 9003 3004 9001 3008 8994
      3006 8992 2998 8994 2999 8997 2997 9000
      2995 9001 2993 8998 2992 8998 2989 9008
      2991 9040 2997 9051 3003 9049

FLASH FLOOD...RADAR INDICATED

$$
4 follow-up statements
102 
WGUS74 KLIX 080942
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
442 AM CDT Thu Apr 8 2021

LAC051-071-089-081145-
/O.CON.KLIX.FF.W.0007.000000T0000Z-210408T1145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
St. Charles LA-Orleans LA-Jefferson LA-
442 AM CDT Thu Apr 8 2021

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 AM CDT FOR
NORTHWESTERN ST. CHARLES...SOUTHWESTERN ORLEANS AND NORTHWESTERN
JEFFERSON PARISHES...

At 441 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Over 3 to 4 inches of rain have already 
fallen. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

IMPACT...Flooding of small creeks and streams, urban areas, 
         highways, streets and underpasses as well as other drainage 
         and low lying areas.

Some locations that will experience flooding include...
New Orleans, Avondale, Metairie, Hahnville, East New Orleans,
Marrero, Harvey, Chalmette, Laplace, Jefferson, Gretna, Harahan,
Westwego, Montz, River Ridge, Ama, Destrehan, St. Rose, Killona and
Norco.

Additional rainfall amounts of up to 1 inch is possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3004 9042 2998 9030 2999 9028 3005 9028
      3002 9013 3004 9003 3004 9001 3008 8994
      3006 8992 2998 8994 2999 8997 2997 9000
      2995 9001 2993 8998 2992 8998 2989 9008
      2991 9040 2997 9051 3003 9049

FLASH FLOOD...RADAR INDICATED

$$

MEFFER
520 
WGUS74 KLIX 081035
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
535 AM CDT Thu Apr 8 2021

LAC089-081045-
/O.CAN.KLIX.FF.W.0007.000000T0000Z-210408T1145Z/
St. Charles LA-
535 AM CDT Thu Apr 8 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN ST. CHARLES 
PARISH...

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

LAT...LON 3005 9028 3002 9018 3002 9013 3003 9006
      3003 9003 3004 9003 3004 9001 3008 8994
      3006 8992 2998 8994 2999 8997 2999 8999
      2995 9001 2993 8998 2992 8998 2989 9008
      2990 9027 2991 9027 2997 9028

$$

LAC051-071-081145-
/O.CON.KLIX.FF.W.0007.000000T0000Z-210408T1145Z/
/00000.U.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson LA-Orleans LA-
535 AM CDT Thu Apr 8 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 AM CDT THIS 
MORNING FOR NORTHWESTERN JEFFERSON AND SOUTHWESTERN ORLEANS 
PARISHES...

At 535 AM CDT, Emergency management reported several impassible 
roadways across New Orleans from Kenner to Gentilly Between 3 and 5 
inches of rain have fallen. Flash flooding is ongoing.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Emergency management.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  New Orleans, Metairie, Marrero, Harvey, Avondale, Chalmette, East 
  New Orleans, Jefferson, Gretna, Harahan, Westwego, Bridge City, 
  Elmwood, River Ridge, Terrytown, Arabi, Waggaman, Ama, St. Rose 
  and Lakefront Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3005 9028 3002 9018 3002 9013 3003 9006
      3003 9003 3004 9003 3004 9001 3008 8994
      3006 8992 2998 8994 2999 8997 2999 8999
      2995 9001 2993 8998 2992 8998 2989 9008
      2990 9027 2991 9027 2997 9028

FLASH FLOOD...OBSERVED

$$
306 
WGUS54 KLIX 081129
FFWLIX
LAC051-071-081345-
/O.EXT.KLIX.FF.W.0007.000000T0000Z-210408T1345Z/
/00000.U.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
629 AM CDT Thu Apr 8 2021

The National Weather Service in New Orleans has extended the

* Flash Flood Warning for...
  Northwestern Jefferson Parish in southeastern Louisiana...
  Southwestern Orleans Parish in southeastern Louisiana...

* Until 845 AM CDT.

* At 629 AM CDT, Emergency management reported several impassible 
  roadways across New Orleans from Kenner to Gentilly. Between 3 and 
  5 inches of rain fell in these areas in a short time this morning. 
  Flooding of some of these areas continues especially some roadways 
  and underpasses.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Emergency management.

  IMPACT...Although no new or further flooding from rainfall is
           expected, areas that have been flooded are still
           draining and continue to pose a hazard.

* Some locations that are experiencing flooding include...
  New Orleans, Metairie, Marrero, Harvey, Avondale, Chalmette, East 
  New Orleans, Jefferson, Gretna, Harahan, Westwego, Bridge City, 
  Elmwood, River Ridge, Terrytown, Arabi, Waggaman, Ama, St. Rose 
  and Lakefront Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 3005 9028 3002 9018 3002 9013 3003 9006
      3003 9003 3004 9003 3004 9001 3008 8994
      3006 8992 2998 8994 2999 8997 2999 8999
      2995 9001 2993 8998 2992 8998 2989 9008
      2990 9027 2991 9027 2997 9028

FLASH FLOOD...OBSERVED

$$

TE
971 
WGUS74 KLIX 081349
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
849 AM CDT Thu Apr 8 2021

LAC051-071-081359-
/O.EXP.KLIX.FF.W.0007.000000T0000Z-210408T1345Z/
/00000.U.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson LA-Orleans LA-
849 AM CDT Thu Apr 8 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR NORTHWESTERN JEFFERSON AND 
SOUTHWESTERN ORLEANS PARISHES...

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

LAT...LON 3005 9028 3002 9018 3002 9013 3003 9006
      3003 9003 3004 9003 3004 9001 3008 8994
      3006 8992 2998 8994 2999 8997 2999 8999
      2995 9001 2993 8998 2992 8998 2989 9008
      2990 9027 2991 9027 2997 9028

$$

DM

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 7, 9:42 PM CDTSevere Thunderstorm WarningLIXPointe Coupee, West Feliciana78 min
Apr 7, 10:22 PM CDTTornado WarningLIXWest Feliciana53 min
Apr 7, 10:50 PM CDTSevere Thunderstorm WarningLIXEast Feliciana, West Feliciana70 min
Apr 8, 12:08 AM CDTSevere Thunderstorm WarningLIXEast Feliciana, Saint Helena67 min
Apr 8, 12:25 AM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, East Feliciana, Pointe Coupee, Saint Helena, West Baton Rouge, West Feliciana34 min
Apr 8, 12:39 AM CDTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa, Washington66 min
Apr 8, 1:05 AM CDTSevere Thunderstorm WarningLIXSaint Tammany, Tangipahoa, Washington55 min
Apr 8, 1:12 AM CDTTornado WarningLIXTangipahoa, Washington33 min
Apr 8, 1:20 AM CDTTornado WarningLIXLivingston, Saint Helena25 min
Apr 8, 1:51 AM CDTSevere Thunderstorm WarningLIXLivingston, Saint John the Baptist, Tangipahoa39 min
Apr 8, 2:00 AM CDTSpecial Marine WarningLIX30 min
Apr 8, 2:04 AM CDTSpecial Weather StatementLIXSaint Tammany56 min
Apr 8, 2:14 AM CDTSpecial Marine WarningLIX61 min
Apr 8, 2:24 AM CDTSevere Thunderstorm WarningLIXSaint Tammany51 min
Apr 8, 2:30 AM CDTTornado WarningLIXSaint Tammany30 min
Apr 8, 2:54 AM CDTSpecial Weather StatementLIXOrleans, Saint Charles66 min
Apr 8, 2:56 AM CDTTornado WarningLIXSaint Tammany34 min
Apr 8, 3:03 AM CDTTornado WarningLIXSaint Charles, Saint John the Baptist14 min
Apr 8, 3:28 AM CDTSpecial Marine WarningLIX62 min
Apr 8, 4:00 AM CDTTornado WarningLIXJefferson12 min
Apr 8, 4:15 AM CDTSpecial Weather StatementLIXJefferson, Lafourche60 min
Apr 8, 4:22 AM CDTTornado WarningLIXJefferson23 min
Apr 8, 4:31 AM CDTSpecial Marine WarningLIX89 min
Apr 8, 5:14 AM CDTSpecial Weather StatementLIXJefferson, Plaquemines, Terrebonne61 min
Apr 8, 5:19 AM CDTSpecial Marine WarningLIX56 min
Apr 8, 5:45 AM CDTSpecial Marine WarningLIX2 hr
Apr 8, 6:11 AM CDTSevere Thunderstorm WarningLIXPlaquemines34 min
Apr 8, 6:15 AM CDTSpecial Marine WarningLIX2 hr
Apr 8, 7:42 AM CDTSpecial Marine WarningLIX63 min
Apr 8, 9:55 AM CDTRiver Flood WarningLIXTangipahoa12 days
Apr 8, 9:58 AM CDTRiver Flood WarningLIXSaint Tammany4 days
Apr 8, 10:10 AM CDTRiver Flood WarningLIXAscension12 days

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.