Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 49, NWS New Orleans, LA

August 16, 2012Orleans Parish, Saint Bernard Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 16, 2012, 3:13 PM CDT for Orleans Parish, Saint Bernard Parish, Louisiana. It was in force for 110 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
Aug 16, 2012, 3:13 PM CDT (20:13 UTC)
Expired
Aug 16, 2012, 5:03 PM CDT
In force
110 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Orleans Parish, LA, Saint Bernard Parish, LA

What was reported inside it

TimeReportWhereRemark
Aug 16, 3:24 PM CDTFLASH FLOOD1 Nw Chalmette, LAST. BERNARD SHERIFFS DEPARTMENT HAS RECEIVED SEVERAL CALLS OF WATER NEAR HOMES IN ARABI AND SEVERAL STREETS IMPASSABLE INCLUDING PORTIONS OF JUDGE PEREZ DRIVE...NORTON STREET AND DOERR DRIVE.

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, 8.2 hours before the alert went out and 40 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 2012-08-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4098 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 2012-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
4098 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
542 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
19 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.

042 
WGUS54 KLIX 162013
FFWLIX
LAC071-087-162315-
/O.NEW.KLIX.FF.W.0049.120816T2013Z-120816T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
313 PM CDT THU AUG 16 2012

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL ORLEANS PARISH IN SOUTHEAST LOUISIANA...
  EXTREME NORTHWESTERN ST. BERNARD PARISH IN SOUTHEAST LOUISIANA...
  THIS INCLUDES THE CITY OF CHALMETTE...

* UNTIL 615 PM CDT

* AT 310 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
  FLASH FLOODING FROM A THUNDERSTORM NEAR CHALMETTE...MOVING
  NORTHEAST AT 5 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

ADDITIONAL RAINFALL AMOUNTS OF ONE INCH ARE POSSIBLE IN THE WARNED 
AREA.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

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.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN NEW
ORLEANS.

&&

LAT...LON 3001 9002 3001 8992 2993 8995 2997 9003

$$

98/SO
1 follow-up statement
736 
WGUS74 KLIX 162203
FFSLIX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
503 PM CDT THU AUG 16 2012

LAC071-087-162211-
/O.CAN.KLIX.FF.W.0049.000000T0000Z-120816T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ORLEANS LA-ST. BERNARD LA-
503 PM CDT THU AUG 16 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EXTREME
NORTHWESTERN ST. BERNARD AND CENTRAL ORLEANS PARISHES...

A FEW LIGHT SPRINKLES ARE STILL OCCURRING ACROSS THE WARNED 
AREA...BUT ALL OF THE HEAVIER RAIN HAS DIMINISHED. ACCORDING TO 
REPORTS RECEIVED FROM THE AREA...THE HIGH WATERS HAVE RECEDED.

LAT...LON 3001 9002 3001 8992 2993 8995 2997 9003

$$

98/SO

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 1:54 PM CDTSpecial Marine WarningLIX66 min
Aug 16, 2:34 PM CDTAreal Flood AdvisoryLIXOrleans, Saint Bernard116 min
Aug 16, 2:57 PM CDTSpecial Marine WarningLIX33 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.