Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 46, NWS New Orleans, LA

August 11, 2012Saint John the Baptist Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 11, 2012, 7:14 AM CDT for Saint John the Baptist Parish, Louisiana. It was in force for 2 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: Aug 11, 2012, 7:14 AM CDT (12:14 UTC)
Expired: Aug 11, 2012, 9:15 AM CDT
In force: 2 hr
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Flood severity: None

County Saint John the Baptist Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 0.2 hours before the alert went out and 87 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1542 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 711 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: -32 m²/s²
Significant tornado parameter: -0.2
Supercell composite: -1.1

Open this sounding in Storm Lab

The text

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

444 
WGUS54 KLIX 111214
FFWLIX
LAC095-111415-
/O.NEW.KLIX.FF.W.0046.120811T1214Z-120811T1415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
714 AM CDT SAT AUG 11 2012

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  ST. JOHN THE BAPTIST PARISH IN SOUTHEAST LOUISIANA...
  THIS INCLUDES THE CITIES OF...RESERVE...LAPLACE...

* UNTIL 915 AM CDT

* AT 709 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
  FLASH FLOODING IS POSSIBLE FROM A THUNDERSTORM OVER THE WARNED
  AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO EDGARD

PRECAUTIONARY/PREPAREDNESS ACTIONS...

RADAR ESTIMATES THAT JUST UNDER 2 INCHES OF RAIN HAS ALREADY FALLEN 
AND AN ADDITIONAL 2 TO 3 INCHES ARE POSSIBLE IN THE WARNED AREA.

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 2990 9066 2995 9067 3016 9064 3018 9043
      3007 9041 3001 9054 3000 9054 3000 9055
      2996 9054 2990 9055

$$

CAB

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 2:55 AM CDT	Special Marine Warning	LIX		95 min
Aug 11, 5:40 AM CDT	Flash Flood Warning	LIX	Saint Tammany	2 hr
Aug 11, 7:55 AM CDT	Flash Flood Warning	LIX	Livingston	95 min
Aug 11, 8:01 AM CDT	Special Marine Warning	LIX		29 min
Aug 11, 8:27 AM CDT	Special Marine Warning	LIX		63 min
Aug 11, 8:36 AM CDT	Special Marine Warning	LIX		24 min
Aug 11, 10:00 AM CDT	Special Marine Warning	LIX		30 min
Aug 11, 10:37 AM CDT	Special Marine Warning	LIX		83 min
Aug 11, 11:26 AM CDT	Special Marine Warning	LIX		34 min
Aug 11, 12:04 PM CDT	Special Marine Warning	LIX		116 min

Nearby

Flash Flood Warnings in Louisiana, 2012 Every 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.