Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 95, NWS New Orleans, LA

August 29, 2021Jefferson Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 29, 2021, 10:48 PM CDT for Jefferson Parish, Louisiana. It was in force for 15 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 29, 2021, 10:48 PM CDT (03:48 UTC)
Expired
Aug 30, 2021, 2:00 PM CDT
In force
15 hr
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Emergency
Flash flood emergency
Damage threat
Catastrophic
Flood severity
None

County Jefferson Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 3.8 hours before the alert went out and 72 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 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 25 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 square meters per square second.1939587897Sfc1 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
25 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
679 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

952 
WGUS54 KLIX 300348
FFWLIX
LAC051-301145-
/O.NEW.KLIX.FF.W.0095.210830T0348Z-210830T1145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
1048 PM CDT Sun Aug 29 2021

...FLASH FLOOD EMERGENCY FOR LAFITTE AND JEAN LAFITTE...

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  Central Jefferson Parish in southeastern Louisiana...

* Until 645 AM CDT Monday.

* At 1048 PM CDT, local law enforcement reported levee failing 
  around Lafitte and Jean Lafitte. Over 200 people in imminent danger

  This is a FLASH FLOOD EMERGENCY for Lafitte and Jean Lafitte. This 
  is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!

  HAZARD...Life threatening flash flooding. Heavy rain and surge
           are leading to a failure of the levee.

  SOURCE...Law enforcement reported.

  IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK
           HIGHER GROUND NOW! Life threatening flash flooding of
           low water crossings, small creeks and streams, urban
           areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Jean Lafitte, Barataria and Lafitte.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now! This is an extremely dangerous and 
life-threatening situation. Do not attempt to travel unless you are 
fleeing an area subject to flooding or under an evacuation order.

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

&&

LAT...LON 2978 9014 2977 9007 2973 9007 2963 9008
      2964 9016 2966 9016 2968 9016 2977 9016

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC

$$

CAB
2 follow-up statements
956 
WGUS54 KLIX 301130
FFWLIX
LAC051-301500-
/O.EXT.KLIX.FF.W.0095.000000T0000Z-210830T1500Z/
/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
630 AM CDT Mon Aug 30 2021

...FLASH FLOOD EMERGENCY FOR LAFITTE AND JEAN LAFITTE...

The National Weather Service in New Orleans has extended the

* Flash Flood Warning for...
  Central Jefferson Parish in southeastern Louisiana...

* Until 1000 AM CDT.

* At 630 AM CDT, local law enforcement reported flash flooding 
  across the warned area. Flash flooding is already occurring.

  This is a FLASH FLOOD EMERGENCY for Lafitte and Jean Lafitte. This 
  is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding.

  SOURCE...Law enforcement reported.

  IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK
           HIGHER GROUND NOW! Life threatening flash flooding of
           low water crossings, small creeks and streams, urban
           areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Jean Lafitte, Barataria and Lafitte.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now! This is an extremely dangerous and 
life-threatening situation. Do not attempt to travel unless you are 
fleeing an area subject to flooding or under an evacuation order.

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

&&

LAT...LON 2978 9014 2977 9007 2973 9007 2963 9008
      2964 9016 2966 9016 2968 9016 2977 9016

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC

$$
066 
WGUS54 KLIX 301459
FFWLIX
LAC051-301900-
/O.EXT.KLIX.FF.W.0095.000000T0000Z-210830T1900Z/
/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
959 AM CDT Mon Aug 30 2021

...FLASH FLOOD EMERGENCY FOR LAFITTE AND JEAN LAFITTE...

The National Weather Service in New Orleans has extended the

* Flash Flood Warning for...
  Central Jefferson Parish in southeastern Louisiana...

* Until 200 PM CDT.

* At 959 AM CDT, local law enforcement reported flash flooding 
  across the warned area. Flash flooding is already occurring.

  This is a FLASH FLOOD EMERGENCY for Lafitte and Jean Lafitte. This 
  is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding.

  SOURCE...Law enforcement reported.

  IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK
           HIGHER GROUND NOW! Life threatening flash flooding of
           low water crossings, small creeks and streams, urban
           areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Jean Lafitte, Barataria and Lafitte.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now! This is an extremely dangerous and 
life-threatening situation. Do not attempt to travel unless you are 
fleeing an area subject to flooding or under an evacuation order.

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

Move to higher ground now. Act quickly to protect your life.

&&

LAT...LON 2978 9014 2977 9007 2973 9007 2963 9008
      2964 9016 2966 9016 2968 9016 2977 9016

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 7:48 PM CDTFlash Flood Warning Considerable damage threatLIXSaint Charles, Saint John the Baptist2 hr
Aug 29, 8:00 PM CDTSpecial Marine WarningLIX30 min
Aug 29, 8:22 PM CDTTornado WarningLIXSaint Tammany38 min
Aug 29, 8:35 PM CDTFlash Flood Warning EmergencyCatastrophic damage threatLIXSaint Charles, Saint John the Baptist6 hr
Aug 29, 8:55 PM CDTFlash Flood Warning EmergencyConsiderable damage threatLIXLivingston, Tangipahoa3 hr
Aug 29, 9:05 PM CDTRiver Flood WarningLIXSaint Tammany12 days
Aug 29, 9:05 PM CDTRiver Flood WarningLIXSaint Tammany21 days
Aug 29, 9:05 PM CDTRiver Flood WarningLIXWashington63 hr
Aug 29, 9:05 PM CDTRiver Flood WarningLIXSaint Tammany, Washington11 days
Aug 29, 10:39 PM CDTSpecial Marine WarningLIX51 min
Aug 29, 10:55 PM CDTSpecial Marine WarningLIX20 min
Aug 29, 11:45 PM CDTFlash Flood Warning EmergencyCatastrophic damage threatLIXPlaquemines10 hr
Aug 29, 11:50 PM CDTFlash Flood Warning Considerable damage threatLIXLivingston, Saint Helena, Saint Tammany, Tangipahoa, Washington3 hr
Aug 30, 12:05 AM CDTFlash Flood Warning EmergencyCatastrophic damage threatLIXLivingston, Tangipahoa12 hr
Aug 30, 1:24 AM CDTFlash Flood WarningLIXLivingston, Saint Helena8 hr
Aug 30, 2:24 AM CDTFlash Flood Warning EmergencyCatastrophic damage threatLIXSaint Charles, Saint John the Baptist8 hr
Aug 30, 2:39 AM CDTFlash Flood Warning Considerable damage threatLIXSaint Tammany9 hr
Aug 30, 2:55 AM CDTFlash Flood Warning Considerable damage threatLIXLivingston, Saint Helena, Saint Tammany, Tangipahoa, Washington5 hr
Aug 30, 3:55 AM CDTFlash Flood WarningLIXEast Feliciana, Saint Helena, Tangipahoa, Washington5 hr
Aug 30, 4:19 AM CDTSmall Craft AdvisoryLIX39 hr
Aug 30, 4:51 AM CDTCoastal Flood AdvisoryLIXAssumption15 hr
Aug 30, 7:15 AM CDTSpecial Marine WarningLIX30 min
Aug 30, 7:18 AM CDTSpecial Marine WarningLIX27 min
Aug 30, 7:45 AM CDTFlash Flood WarningLIXLivingston, Saint Helena, Saint Tammany, Tangipahoa, Washington3 hr
Aug 30, 9:01 AM CDTSpecial Marine WarningLIX89 min
Aug 30, 9:58 AM CDTAreal Flood WarningLIXJefferson, Lafourche, Livingston, Plaquemines, Saint Charles, Saint James and 1 more60 hr
Aug 30, 10:53 AM CDTAreal Flood WarningLIXSaint Tammany, Tangipahoa, Washington35 hr
Aug 30, 11:04 AM CDTAreal Flood WarningLIXSaint Helena, Saint Tammany, Tangipahoa, Washington35 hr
Aug 30, 11:34 AM CDTAreal Flood WarningLIXSaint Tammany, Washington34 hr
Aug 30, 12:24 PM CDTAreal Flood WarningLIXAscension, Livingston, Saint John the Baptist, Saint Tammany, Tangipahoa33 hr
Aug 30, 2:57 PM CDTHeat AdvisoryLIXAssumption, East Baton Rouge, Iberville, Orleans, Saint Bernard, Saint James and 2 more26 hr
Aug 30, 6:10 PM CDTSpecial Marine WarningLIX95 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.