Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 93, NWS New Orleans, LA

August 29, 2021Saint Charles Parish, Saint John the Baptist Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 29, 2021, 8:35 PM CDT for Saint Charles Parish, Saint John the Baptist Parish, Louisiana. It was in force for 6 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, 8:35 PM CDT (01:35 UTC)
Expired
Aug 30, 2021, 2:30 AM CDT
In force
6 hr
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Emergency
Flash flood emergency
Damage threat
Catastrophic
Flood severity
None

Counties Saint Charles Parish, LA, Saint John the Baptist Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 1.6 hours before the alert went out and 79 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.

456 
WGUS54 KLIX 300135
FFWLIX
LAC089-095-300530-
/O.NEW.KLIX.FF.W.0093.210830T0135Z-210830T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

...FLASH FLOOD EMERGENCY FOR LAPLACE...

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  St. Charles Parish in southeastern Louisiana...
  St. John The Baptist Parish in southeastern Louisiana...

* Until 1230 AM CDT.

* At 835 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 6 and 10 inches of rain 
  have fallen. Additional rainfall amounts of 4 to 6 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

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

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  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...
  Hahnville, Laplace, Reserve, Killona, Taft, Montz, Norco, New 
  Sarpy, Edgard, Destrehan, Boutte, Paradis, Luling, St. Rose, 
  Garyville, Bayou Gauche, Des Allemands, Ama and Wallace.

This includes the following Interstates...
	Interstate 55 in Louisiana between mile markers 1 and 6.
	Interstate 10 in Louisiana between mile markers 198 and 212...and
	between mile markers 215 and 220.
	Interstate 310 between mile markers 1 and 11.

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 3018 9064 3017 9054 3018 9043 3012 9043
      3007 9040 3006 9038 3005 9029 2979 9031
      2981 9047 2987 9048 2990 9053 2990 9064

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC

$$
2 follow-up statements
019 
WGUS74 KLIX 300245
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
945 PM CDT Sun Aug 29 2021

LAC089-095-300530-
/O.CON.KLIX.FF.W.0093.000000T0000Z-210830T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
St. Charles LA-St. John The Baptist LA-
945 PM CDT Sun Aug 29 2021

...FLASH FLOOD EMERGENCY FOR LAPLACE...

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM CDT MONDAY 
FOR ST. CHARLES AND ST. JOHN THE BAPTIST PARISHES...

At 945 PM CDT, Doppler radar indicated Ida's eyewall producing very 
heavy rain in LaPlace. Reports coming in of people trapped in homes 
in LaPlace. Water completely surrounding a hotel. Numerous people 
requesting to be rescued. Between 6 and 12 inches of rain have 
fallen. Additional rainfall amounts of 4 to 6 inches are possible in 
the warned area. Flash flooding is ongoing or expected to begin 
shortly.

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

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

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...
  Hahnville, Laplace, Reserve, Killona, Taft, Montz, Norco, New 
  Sarpy, Edgard, Destrehan, Boutte, Paradis, Luling, St. Rose, 
  Garyville, Bayou Gauche, Des Allemands, Ama and Wallace.

This includes the following Interstates...
	Interstate 55 in Louisiana between mile markers 1 and 6.
	Interstate 10 in Louisiana between mile markers 198 and 212...and
	between mile markers 215 and 220.
	Interstate 310 between mile markers 1 and 11.

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.

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

&&

LAT...LON 3018 9064 3017 9054 3018 9043 3012 9043
      3007 9040 3006 9038 3005 9029 2979 9031
      2981 9047 2987 9048 2990 9053 2990 9064

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC

$$

CAB
060 
WGUS54 KLIX 300515
FFWLIX
LAC089-095-300730-
/O.EXT.KLIX.FF.W.0093.000000T0000Z-210830T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
1215 AM CDT Mon Aug 30 2021

...FLASH FLOOD EMERGENCY FOR LAPLACE...

The National Weather Service in New Orleans has extended the

* Flash Flood Warning for...
  St. Charles Parish in southeastern Louisiana...
  St. John The Baptist Parish in southeastern Louisiana...

* Until 230 AM CDT.

* At 1215 AM CDT, emergency management reported thunderstorms 
  producing heavy rain in People trapped on the top of homes, roads 
  completely flooded, and high water rescues are trying to get out. 
  . Between 6 and 13 inches of rain have fallen. Additional rainfall 
  amounts of 1 to 2 inches are possible in the warned area. Flash 
  flooding is ongoing from the combination of heavy rain and storm 
  surge.

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

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Emergency management 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...
  Hahnville, Laplace, Reserve, Killona, Taft, Montz, Norco, New 
  Sarpy, Edgard, Destrehan, Boutte, Paradis, Luling, St. Rose, 
  Garyville, Bayou Gauche, Des Allemands, Ama and Wallace.

This includes the following Interstates...
	Interstate 55 in Louisiana between mile markers 1 and 6.
	Interstate 10 in Louisiana between mile markers 198 and 212...and
	between mile markers 215 and 220.
	Interstate 310 between mile markers 1 and 11.

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.

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

&&

LAT...LON 3018 9064 3017 9054 3018 9043 3012 9043
      3007 9040 3006 9038 3005 9029 2979 9031
      2981 9047 2987 9048 2990 9053 2990 9064

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

$$

CAB

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, 8:55 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, 10:48 PM CDTFlash Flood Warning EmergencyCatastrophic damage threatLIXJefferson15 hr
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.