Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 8, NWS Lake Charles, LA

May 11, 2021Calcasieu Parish, Louisiana

NWS Lake Charles, LA issued this flash flood warning at May 11, 2021, 9:32 PM CDT for Calcasieu Parish, Louisiana. It was in force for 3 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
May 11, 2021, 9:32 PM CDT (02:32 UTC)
Expired
May 12, 2021, 12:30 AM CDT
In force
3 hr
Issued by
NWS Lake Charles, LA
Area
Storm-based polygon
Flood severity
None

County Calcasieu Parish, LA

The radar

The Lake Charles radar (KLCH), 10 km from the middle of the area, began a volume at 02:36 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 2.5 hours before the alert went out and 11 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, Lake Charles Mun, LA at 00:00Z on 2021-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2262 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 00:00Z on 2021-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.19395878Sfc1 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
2262 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
759 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
131 m²/s²
Significant tornado parameter
1.8
Supercell composite
12.5

Open this sounding in Storm Lab

The text

As transmitted.

826 
WGUS54 KLCH 120232
FFWLCH
LAC019-120530-
/O.NEW.KLCH.FF.W.0008.210512T0232Z-210512T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Lake Charles LA
932 PM CDT Tue May 11 2021

The National Weather Service in Lake Charles has issued a

* Flash Flood Warning for...
  South Central Calcasieu Parish in southwestern Louisiana...

* Until 1230 AM CDT.

* At 932 PM CDT, Thunderstorms producing heavy rain have been 
  occurring across the warned area. Between 1 and 4 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Public.

  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...
  Lake Charles, Sulphur, Westlake and Carlyss.

Additional rainfall amounts of 1 to 2 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 3019 9341 3026 9319 3018 9310 3007 9337

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...1-2 INCHES IN 3 HOURS 

$$

24

The office that day

Everything else NWS Lake Charles, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 11, 7:23 PM CDTSevere Thunderstorm WarningLCHCalcasieu37 min
May 11, 7:28 PM CDTSevere Thunderstorm WarningLCHIberia, Saint Martin, St. Mary31 min
May 11, 7:46 PM CDTSpecial Weather StatementLCHAcadia44 min
May 11, 7:56 PM CDTSpecial Weather StatementLCHJefferson Davis34 min
May 11, 7:58 PM CDTSpecial Weather StatementLCHCalcasieu47 min
May 11, 8:06 PM CDTSpecial Weather StatementLCHBeauregard39 min
May 11, 8:16 PM CDTSpecial Weather StatementLCHCalcasieu29 min
May 11, 8:31 PM CDTSpecial Weather StatementLCHAllen, Rapides44 min
May 11, 8:32 PM CDTSpecial Marine WarningLCH28 min
May 11, 8:45 PM CDTSpecial Weather StatementLCHCameron45 min
May 11, 8:58 PM CDTSpecial Marine WarningLCH47 min
May 11, 9:18 PM CDTSpecial Weather StatementLCHEvangeline, Jefferson Davis42 min
May 11, 9:36 PM CDTFlash Flood WarningLCHAcadia, Iberia, Jefferson Davis, Lafayette, Saint Landry, Saint Martin and 1 more4 hr
May 11, 9:39 PM CDTSpecial Weather StatementLCHCameron51 min
May 11, 10:19 PM CDTSpecial Weather StatementLCHLafayette, Vermilion41 min
May 11, 10:59 PM CDTSpecial Marine WarningLCH61 min
May 11, 11:13 PM CDTSpecial Weather StatementLCHSaint Martin47 min
May 11, 11:49 PM CDTSevere Thunderstorm WarningLCHSaint Martin, St. Mary41 min
May 12, 1:38 AM CDTAreal Flood WarningLCHAcadia, Iberia, Jefferson Davis, Lafayette, Saint Landry, Saint Martin and 2 more3 hr
May 12, 11:16 AM CDTRiver Flood WarningLCHAcadia, Allen, Evangeline, Jefferson Davis4 days
May 12, 3:22 PM CDTRiver Flood WarningLCHAcadia, Evangeline, Saint Landry56 hr
May 12, 3:22 PM CDTRiver Flood WarningLCHAcadia, Jefferson Davis, Vermilion31 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.