Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 34, NWS New Orleans, LA

July 19, 2012Saint Tammany Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Jul 19, 2012, 5:03 PM CDT for Saint Tammany Parish, Louisiana. It was in force for 117 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
Jul 19, 2012, 5:03 PM CDT (22:03 UTC)
Expired
Jul 19, 2012, 7:00 PM CDT
In force
117 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

County Saint Tammany Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 10.1 hours before the alert went out and 6 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 2012-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2009 joules per kilogram.LCLLFCEL10008507005003002001001 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, Slidell Radar S, LA at 12:00Z on 2012-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
2009 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
654 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
79 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.

841 
WGUS54 KLIX 192203
FFWLIX
LAC103-200000-
/O.NEW.KLIX.FF.W.0034.120719T2203Z-120720T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
503 PM CDT THU JUL 19 2012

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN ST. TAMMANY PARISH IN SOUTHEAST LOUISIANA...
  THIS INCLUDES THE CITIES OF...SLIDELL...EDEN ISLE...

* UNTIL 700 PM CDT

* AT 454 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED  
  TO DETECT FLASH FLOODING ACROSS SOUTHEASTERN ST TAMMANY PARISH 
  FROM HEAVY RAINFALL EARLIER THIS AFTERNOON. IT WILL LIKELY TAKE
  AT LEAST ANOTHER HOUR OR 2 FOR THE FLOODING TO SUBSIDE. ANY ADDITIONAL
  RAINFALL WILL EXACERBATE THE SITUATION. SLIDELL APPEARS TO BE THE CITY
  WITH GREATEST IMPACTS. MOTORISTS SHOULD AVOID WATER COVERED ROADWAYS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PEARL RIVER
  AND LACOMBE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

&&

LAT...LON 3037 8966 3034 8963 3031 8963 3029 8965
      3028 8963 3025 8963 3021 8960 3015 8961
      3023 8986 3025 8989 3025 8995 3033 9004
      3047 9000

$$
1 follow-up statement
315 
WGUS74 KLIX 200000
FFSLIX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
700 PM CDT THU JUL 19 2012

LAC103-200011-
/O.EXP.KLIX.FF.W.0034.000000T0000Z-120720T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ST. TAMMANY LA-
700 PM CDT THU JUL 19 2012

...THE FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHEASTERN ST. TAMMANY
PARISH...

LAT...LON 3037 8966 3034 8963 3031 8963 3029 8965
      3028 8963 3025 8963 3021 8960 3015 8961
      3023 8986 3025 8989 3025 8995 3033 9004
      3047 9000

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 8:22 PM CDTSpecial Marine WarningLIX23 min
Jul 18, 8:30 PM CDTAreal Flood AdvisoryLIXSaint Tammany2 hr
Jul 18, 8:42 PM CDTSpecial Marine WarningLIX48 min
Jul 18, 8:51 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines114 min
Jul 19, 8:45 AM CDTSpecial Marine WarningLIX30 min
Jul 19, 12:05 PM CDTSpecial Marine WarningLIX40 min
Jul 19, 12:43 PM CDTSpecial Marine WarningLIX62 min
Jul 19, 1:13 PM CDTSpecial Marine WarningLIX32 min
Jul 19, 2:17 PM CDTAreal Flood AdvisoryLIXSaint Tammany118 min
Jul 19, 2:50 PM CDTSpecial Marine WarningLIX55 min
Jul 19, 2:56 PM CDTFlash Flood WarningLIXSaint Tammany2 hr
Jul 19, 3:37 PM CDTFlash Flood WatchLIXAssumption, East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Bernard and 7 more49 hr
Jul 19, 3:43 PM CDTFlash Flood WarningLIXSaint Tammany2 hr
Jul 19, 4:12 PM CDTAreal Flood AdvisoryLIXLivingston, Saint Helena, Tangipahoa2 hr
Jul 19, 5:48 PM CDTAreal Flood AdvisoryLIXSaint Charles, Saint James, Saint John the Baptist117 min
Jul 19, 6:03 PM CDTFlash Flood WarningLIXSaint Charles, Saint John the Baptist3 hr
Jul 19, 6:30 PM CDTAreal Flood AdvisoryLIXAscension, Assumption, Iberville2 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.