Alert archive / Louisiana / Flash Flood Warnings in 1987

Flash Flood Warning 3, NWS New Orleans, LA

August 2, 1987Saint Tammany Parish, Washington Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 2, 1987, 7:47 PM CDT for Saint Tammany Parish, Washington Parish, Louisiana. It was in force for 48 min.

The area

The counties it named.

The facts

Issued
Aug 2, 1987, 7:47 PM CDT (00:47 UTC)
Expired
Aug 2, 1987, 8:35 PM CDT
In force
48 min
Issued by
NWS New Orleans, LA
Area
Whole counties

Counties Saint Tammany Parish, LA, Washington Parish, LA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Boothville, LA (KBVE), launched 00:00Z, 0.8 hours before the alert went out and 156 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, Boothville, LA at 00:00Z on 1987-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2421 joules per kilogram.LCLEL10008507005003002001001 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, Boothville, LA at 00:00Z on 1987-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 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
2421 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
947 m above ground
0-6 km bulk shear
0 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
0 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.

000 
TTAA00 KNEW 030044
FFWNEW
LAC103-117-030245-
 
BULLETIN - EBS ACTIVATION REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
747 PM CDT SUN AUG 2 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  945 PM CDT AND A
FLASH FLOOD WARNING EFFECTIVE UNTIL  945 PM CDT
FOR PEOPLE IN THE FOLLOWING PARISHES...
 
IN SOUTHEAST LOUISIANA
          ...NORTHERN ST.TAMMANY...SOUTHERN WASHINGTON
 
WEATHER SERVICE RADAR SHOWS A CLUSTER OF VERY STRONG THUNDERSTORMS
BETWEEN BOGALUSA AND SUN ALONG THE ST. TAMMANY WASHINGTON PARISH
LINE. THE THUNDERSTORMS ARE MOVING SLOWLY TOWARNDS THE SOUTH ABOUT
5 MPH.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHEL\TER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 7:47 PM CDTSevere Thunderstorm WarningLIXSaint Tammany, Washington48 min
Aug 2, 8:13 PM CDTSevere Thunderstorm WarningLIXSaint Tammany62 min

Nearby

Flash Flood Warnings in Louisiana, 1987Every flash flood warning in 1987

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.