Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 71, NWS New Orleans, LA

August 30, 2012Saint Tammany Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 30, 2012, 9:43 AM CDT for Saint Tammany Parish, Louisiana. It was in force for 3 hr. 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 30, 2012, 9:43 AM CDT (14:43 UTC)
Expired
Aug 30, 2012, 12:45 PM CDT
In force
3 hr
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

County Saint Tammany Parish, LA

What was reported inside it

TimeReportWhereRemark
Aug 30, 11:52 AM CDTFLASH FLOODSlidell, LACITY OFFICIALS REPORTED SIGNIFICANT STORM SURGE AND FLASH FLOODING IN SLIDELL. 18 INCHES TO 3 FEET WATER REPORTED IN OLD TOWN. WATER STILL RISING IN DELLWOOD AREA NEAR INTERSECTION OF FRONT STREET AND PONTCHARTRAIN 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, 2.7 hours before the alert went out and 13 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 2012-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2012-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 282 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
0 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
282 m²/s²
0-3 km storm-relative helicity
332 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.4

Open this sounding in Storm Lab

The text

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

527 
WGUS54 KLIX 301443
FFWLIX
LAC103-301745-
/O.NEW.KLIX.FF.W.0071.120830T1443Z-120830T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
943 AM CDT THU AUG 30 2012

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

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

* UNTIL 1245 PM CDT

* AT 940 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAINFALL IS EXPECTED TO RESULT IN FLASH FLOODING ACROSS 
  THE SLIDELL AREA. HEAVY RAINFALL WILL ALSO IMPEDE DRAINAGE OF
  FLOOD WATER IN THE CENTRAL AND SOUTH CITY LIMITS OF SLIDELL. 

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 3031 8970 3023 8972 3019 8977 3022 8985
      3024 8987 3025 8989 3024 8993 3025 8998
      3027 9000 3047 8977

$$

22/TD
1 follow-up statement
011 
WGUS74 KLIX 301745
FFSLIX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1245 PM CDT THU AUG 30 2012

LAC103-301750-
/O.EXP.KLIX.FF.W.0071.000000T0000Z-120830T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ST. TAMMANY LA-
1245 PM CDT THU AUG 30 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1245 PM CDT FOR SOUTH
CENTRAL ST. TAMMANY PARISH...

SURGE FLOODING OF LOW LYING AREAS IN OLD TOWN SLIDELL WILL CONTINUE 
THROUGH THE AFTERNOON BUT WILL SLOWLY RECEDE. ADDITIONAL SHOWERS ARE 
EXPECTED THROUGH THE AFTERNOON.  DO NOT DRIVE INTO AREAS WHERE WATER 
COVERS THE ROAD!

A TORNADO WATCH REMAINS IN EFFECT UNTIL 400 PM CDT THURSDAY AFTERNOON
FOR SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI.

LAT...LON 3031 8970 3023 8972 3019 8977 3022 8985
      3024 8987 3025 8989 3024 8993 3025 8998
      3027 9000 3047 8977

$$


DUNN

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 7:09 PM CDTFlash Flood WarningLIXAscension, East Baton Rouge, Livingston, Tangipahoa6 hr
Aug 29, 7:42 PM CDTFlash Flood WarningLIXSaint Tammany, Washington4 hr
Aug 29, 10:54 PM CDTRiver Flood WarningLIXEast Baton Rouge23 hr
Aug 29, 11:02 PM CDTRiver Flood WarningLIXEast Baton Rouge, Livingston4 days
Aug 29, 11:14 PM CDTRiver Flood WarningLIXEast Baton Rouge6 days
Aug 29, 11:16 PM CDTRiver Flood WarningLIXSaint Helena58 hr
Aug 29, 11:20 PM CDTRiver Flood WarningLIXSaint Helena69 hr
Aug 29, 11:22 PM CDTRiver Flood WarningLIXLivingston3 days
Aug 29, 11:31 PM CDTRiver Flood WarningLIXTangipahoa58 hr
Aug 29, 11:38 PM CDTRiver Flood WarningLIXSaint Tammany3 days
Aug 29, 11:45 PM CDTFlash Flood WarningLIXWashington5 hr
Aug 29, 11:47 PM CDTRiver Flood WarningLIXSaint Tammany47 hr
Aug 30, 12:06 AM CDTRiver Flood WarningLIXTangipahoa71 hr
Aug 30, 1:52 AM CDTFlash Flood WarningLIXSaint Tammany3 hr
Aug 30, 4:58 AM CDTFlash Flood Warning EmergencyLIXSaint Tammany4 hr
Aug 30, 8:01 AM CDTRiver Flood WarningLIXAscension, Livingston7 days
Aug 30, 8:01 AM CDTRiver Flood WarningLIXLivingston6 days
Aug 30, 9:17 AM CDTTornado WarningLIXOrleans, Saint Tammany28 min
Aug 30, 9:42 AM CDTRiver Flood WarningLIXAscension, Livingston5 days
Aug 30, 11:11 AM CDTFlash Flood Warning EmergencyLIXTangipahoa3 hr
Aug 30, 1:20 PM CDTFlash Flood WarningLIXSaint Charles, Saint John the Baptist3 hr
Aug 30, 4:21 PM CDTCoastal Flood WarningLIXSaint Bernard, Saint James, Saint John the Baptist49 hr
Aug 30, 4:34 PM CDTRiver Flood WarningLIXTangipahoa48 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.