Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 131, NWS New Orleans, LA

December 6, 2021Ascension Parish, East Baton Rouge Parish, West Baton Rouge Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Dec 6, 2021, 2:51 PM CST for Ascension Parish, East Baton Rouge Parish, West Baton Rouge Parish, Louisiana. It was in force for 116 min. 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
Dec 6, 2021, 2:51 PM CST (20:51 UTC)
Expired
Dec 6, 2021, 4:47 PM CST
In force
116 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Ascension Parish, LA, East Baton Rouge Parish, LA, West Baton Rouge Parish, LA

What was reported inside it

TimeReportWhereRemark
Dec 6, 2:55 PM CSTFLASH FLOOD3 Wnw Baton Rouge, LAEM REPORTS I-10 AT THE GOVERNORS MANSION IS CLOSED DUE TO HIGH WATER.

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, 8.9 hours before the alert went out and 137 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 2021-12-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 720 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 2021-12-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 180 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
720 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
680 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
180 m²/s²
0-3 km storm-relative helicity
201 m²/s²
Significant tornado parameter
0.5
Supercell composite
5.4

Open this sounding in Storm Lab

The text

As transmitted.

301 
WGUS54 KLIX 062051
FFWLIX
LAC005-033-121-070000-
/O.NEW.KLIX.FF.W.0131.211206T2051Z-211207T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
251 PM CST Mon Dec 6 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  Northwestern Ascension Parish in southeastern Louisiana...
  South Central East Baton Rouge Parish in southeastern Louisiana...
  Southeastern West Baton Rouge Parish in southeastern Louisiana...

* Until 600 PM CST.

* At 251 PM CST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing.

  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...
  Baton Rouge, Denham Springs, Port Allen, Oak Hills Place, 
  Westminster, Inniswold, Gardere, Village St. George, Old Jefferson 
  and Shenandoah.

This includes the following Interstates...
	Interstate 10 in Louisiana between mile markers 154 and 168.
	Interstate 12 between mile markers 1 and 8.
	Interstate 110 in Louisiana between mile markers 1 and 3.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3048 9122 3048 9120 3048 9104 3048 9099
      3046 9099 3033 9099 3032 9114 3032 9115
      3032 9122

FLASH FLOOD...RADAR INDICATED

$$

MW
1 follow-up statement
798 
WGUS74 KLIX 062247
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
447 PM CST Mon Dec 6 2021

LAC005-033-121-062257-
/O.CAN.KLIX.FF.W.0131.000000T0000Z-211207T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ascension LA-East Baton Rouge LA-West Baton Rouge LA-
447 PM CST Mon Dec 6 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN ASCENSION, 
SOUTH CENTRAL EAST BATON ROUGE AND SOUTHEASTERN WEST BATON ROUGE 
PARISHES...

The heavy rain has ended. Light rain will continue, but flooding is 
no longer expected to pose a threat. Please continue to heed any 
remaining road closures.

LAT...LON 3048 9122 3048 9120 3048 9104 3048 9099
      3046 9099 3033 9099 3032 9114 3032 9115
      3032 9122

$$

DM

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 6, 11:08 AM CSTSpecial Weather StatementLIXEast Feliciana67 min
Dec 6, 12:01 PM CSTSpecial Weather StatementLIXSaint Helena74 min
Dec 6, 12:21 PM CSTSevere Thunderstorm WarningLIXEast Feliciana, Saint Helena54 min
Dec 6, 12:46 PM CSTSevere Thunderstorm WarningLIXTangipahoa, Washington59 min
Dec 6, 1:22 PM CSTTornado WarningLIXTangipahoa, Washington68 min
Dec 6, 1:29 PM CSTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa, Washington61 min
Dec 6, 1:40 PM CSTSpecial Weather StatementLIXSaint Helena65 min
Dec 6, 1:44 PM CSTSevere Thunderstorm WarningLIXLivingston, Saint Helena61 min
Dec 6, 1:54 PM CSTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa66 min
Dec 6, 2:21 PM CSTSevere Thunderstorm WarningLIXSaint Tammany, Washington39 min
Dec 6, 2:24 PM CSTTornado WarningLIXWashington21 min
Dec 6, 2:30 PM CSTSevere Thunderstorm WarningLIXLivingston, Saint Tammany, Tangipahoa60 min
Dec 6, 2:35 PM CSTTornado WarningLIXSaint Tammany, Washington55 min
Dec 6, 2:41 PM CSTSpecial Marine WarningLIX64 min
Dec 6, 2:51 PM CSTTornado WarningLIXSaint Tammany39 min
Dec 6, 2:56 PM CSTTornado WarningLIXSaint Tammany49 min
Dec 6, 3:09 PM CSTSevere Thunderstorm Warning Considerable damage threatLIXSaint Tammany66 min
Dec 6, 3:20 PM CSTTornado WarningLIXSaint Tammany30 min
Dec 6, 3:26 PM CSTSpecial Marine WarningLIX64 min
Dec 6, 4:14 PM CSTSpecial Marine WarningLIX91 min
Dec 6, 5:24 PM CSTSpecial Marine WarningLIX66 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.