Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS New Orleans, LA

February 11, 2021East Baton Rouge Parish, East Feliciana Parish, Saint Helena Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Feb 11, 2021, 6:41 AM CST for East Baton Rouge Parish, East Feliciana Parish, Saint Helena Parish, Louisiana. It was in force for 3 hr. 1 report 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
Feb 11, 2021, 6:41 AM CST (12:41 UTC)
Expired
Feb 11, 2021, 9:45 AM CST
In force
3 hr
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties East Baton Rouge Parish, LA, East Feliciana Parish, LA, Saint Helena Parish, LA

What was reported inside it

TimeReportWhereRemark
Feb 11, 8:00 AM CSTFLASH FLOODClinton, LAREPORTS OF FLOODED ROADS ACROSS PORTIONS OF EAST FELICIANA PARISH. REPORT OF 6.47 INCHES OF RAIN IN CLINTON BETWEEN MIDNIGHT AND 8AM.

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 12:00Z, 0.7 hours before the alert went out and 145 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 2021-02-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1397 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 2021-02-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 140 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
1397 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
571 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
140 m²/s²
0-3 km storm-relative helicity
182 m²/s²
Significant tornado parameter
1.0
Supercell composite
7.5

Open this sounding in Storm Lab

The text

As transmitted.

408 
WGUS54 KLIX 111241
FFWLIX
LAC033-037-091-111545-
/O.NEW.KLIX.FF.W.0001.210211T1241Z-210211T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
641 AM CST Thu Feb 11 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  Northwestern East Baton Rouge Parish in southeastern Louisiana...
  East Feliciana Parish in southeastern Louisiana...
  Northwestern St. Helena Parish in southeastern Louisiana...

* Until 945 AM CST.

* At 641 AM CST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 5 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...
  Zachary, Jackson, Clinton, Slaughter, Wilson, Felps and Darlington.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3065 9130 3069 9132 3085 9121 3096 9102
      3099 9092 3100 9068 3087 9077 3066 9104
      3060 9125

FLASH FLOOD...RADAR INDICATED

$$
1 follow-up statement
909 
WGUS74 KLIX 111308
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
708 AM CST Thu Feb 11 2021

LAC033-037-091-111545-
/O.CON.KLIX.FF.W.0001.000000T0000Z-210211T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
East Baton Rouge LA-East Feliciana LA-St. Helena LA-
708 AM CST Thu Feb 11 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 AM CST THIS 
MORNING FOR NORTHWESTERN EAST BATON ROUGE, EAST FELICIANA AND 
NORTHWESTERN ST. HELENA PARISHES...

At 708 AM CST, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 3 and 5 inches of rain have 
fallen. Flash flooding is ongoing or expected to begin shortly.

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

SOURCE...Doppler radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Zachary, Jackson, Clinton, Slaughter, Wilson, Felps and Darlington.

Additional rainfall amounts of 1 to 3 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 3065 9130 3069 9132 3085 9121 3096 9102
      3099 9092 3100 9068 3087 9077 3066 9104
      3060 9125

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 11, 2:58 AM CSTSpecial Weather StatementLIXWest Baton Rouge47 min
Feb 11, 3:45 AM CSTSpecial Weather StatementLIXWest Feliciana45 min
Feb 11, 4:05 AM CSTSpecial Weather StatementLIXWest Feliciana40 min
Feb 11, 5:11 AM CSTSpecial Weather StatementLIXEast Feliciana34 min
Feb 11, 5:46 AM CSTSpecial Weather StatementLIXEast Feliciana, Saint Helena29 min
Feb 11, 7:22 AM CSTSpecial Weather StatementLIXSaint Helena53 min
Feb 11, 8:51 AM CSTSpecial Weather StatementLIXWashington54 min
Feb 11, 9:10 AM CSTTornado WarningLIXWashington28 min
Feb 11, 9:35 AM CSTAreal Flood AdvisoryLIXAscension, East Baton Rouge, East Feliciana, Iberville, Livingston, Pointe Coupee and 4 more3 hr
Feb 11, 10:20 AM CSTSpecial Weather StatementLIXLivingston, Saint James, Saint John the Baptist55 min
Feb 11, 10:27 AM CSTAreal Flood AdvisoryLIXAscension, Livingston, Saint Helena, Saint James, Saint John the Baptist, Saint Tammany and 2 more3 hr
Feb 11, 11:06 AM CSTAreal Flood AdvisoryLIXSaint Tammany, Tangipahoa, Washington2 hr
Feb 11, 11:15 AM CSTSpecial Weather StatementLIXSaint Tammany60 min
Feb 11, 11:26 AM CSTRiver Flood WarningLIXSaint Tammany19 days
Feb 11, 11:26 AM CSTRiver Flood WarningLIXSaint Tammany, Washington4 days
Feb 11, 11:26 AM CSTRiver Flood WarningLIXSaint Tammany5 days
Feb 11, 11:35 AM CSTAreal Flood AdvisoryLIXAssumption, Jefferson, Lafourche, Saint Charles, Saint James, Saint John the Baptist and 1 more3 hr
Feb 11, 12:04 PM CSTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines, Saint Bernard, Saint Charles3 hr
Feb 11, 2:00 PM CSTRiver Flood WarningLIXEast Baton Rouge52 hr

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.