Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 20, NWS New Orleans, LA

May 2, 2012Ascension Parish, Livingston Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at May 2, 2012, 5:04 PM CDT for Ascension Parish, Livingston Parish, Louisiana. It was in force for 116 min. 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 2, 2012, 5:04 PM CDT (22:04 UTC)
Expired
May 2, 2012, 7:00 PM CDT
In force
116 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Ascension Parish, LA, Livingston Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 10.1 hours before the alert went out and 113 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 2012-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2546 joules per kilogram.LCLEL10008507005003002001001 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 2012-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 square meters per square second.1939Sfc1 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
2546 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
482 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

666 
WGUS54 KLIX 022204
FFWLIX
LAC005-063-030000-
/O.NEW.KLIX.FF.W.0020.120502T2204Z-120503T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
504 PM CDT WED MAY 2 2012

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL ASCENSION PARISH IN SOUTHEAST LOUISIANA...
  THIS INCLUDES THE CITY OF GONZALES...
  SOUTH CENTRAL LIVINGSTON PARISH IN SOUTHEAST LOUISIANA...

* UNTIL 700 PM CDT

* AT 459 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  FLASH FLOODING FROM A CLUSTER OF THUNDERSTORMS OVER THE WARNED     
  AREA. RADAR ESTIMATES NEAR 3 INCHES HAVE OCCURRED NEAR PORT        
  VINCENT SINCE 4 PM. DUE TO THE SLOW MOVEMENT...AN ADDITIONAL 1 TO  
  2 INCHES WILL CAUSE FLOODING IN AND NEAR PORT VINCENT AND SOUTHERN 
  PORTION OF THE BATON ROUGE METRO AREA. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 3039 9073 3021 9073 3021 9094 3034 9094
      3034 9091 3035 9090 3037 9092 3036 9094
      3039 9094

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 2, 6:17 AM CDTSpecial Marine WarningLIX43 min
May 2, 7:42 AM CDTSpecial Marine WarningLIX63 min
May 2, 8:39 AM CDTSpecial Marine WarningLIX36 min
May 2, 10:03 AM CDTSpecial Marine WarningLIX57 min
May 2, 2:13 PM CDTAreal Flood AdvisoryLIXTangipahoa2 hr
May 2, 3:21 PM CDTFlash Flood WarningLIXTangipahoa114 min
May 2, 4:15 PM CDTAreal Flood AdvisoryLIXAscension, Livingston2 hr
May 2, 4:38 PM CDTAreal Flood AdvisoryLIXEast Baton Rouge, Iberville112 min
May 2, 5:09 PM CDTFlash Flood WarningLIXAscension, East Baton Rouge, Iberville2 hr
May 2, 6:09 PM CDTAreal Flood AdvisoryLIXLivingston111 min
May 2, 6:21 PM CDTFlash Flood WatchLIXAssumption, Saint Bernard, Saint James, Saint John the Baptist6 hr

Nearby

Flash Flood Warnings in Louisiana, 2012Every flash flood warning in 2012

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.