Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 33, NWS Shreveport, LA

August 17, 2012Ouachita Parish, Louisiana

NWS Shreveport, LA issued this flash flood warning at Aug 17, 2012, 8:18 AM CDT for Ouachita Parish, Louisiana. It was in force for 94 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: Aug 17, 2012, 8:18 AM CDT (13:18 UTC)
Expired: Aug 17, 2012, 9:52 AM CDT
In force: 94 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Flood severity: None

County Ouachita Parish, LA

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 1.3 hours before the alert went out and 155 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: 112 J/kg
Mixed-layer CIN: -145 J/kg
Mixed-layer LCL: 1226 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -87 m²/s²
0-3 km storm-relative helicity: -41 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.

614 
WGUS54 KSHV 171318
FFWSHV
LAC073-171715-
/O.NEW.KSHV.FF.W.0033.120817T1318Z-120817T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
818 AM CDT FRI AUG 17 2012

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  OUACHITA PARISH IN NORTH CENTRAL LOUISIANA...
  THIS INCLUDES THE CITIES OF...WEST MONROE...SWARTZ...MONROE...
  CLAIBORNE...BROWNSVILLE-BAWCOMVILLE...

* UNTIL 1215 PM CDT

* AT 812 AM CDT...THE PUBLIC REPORTED VERY HEAVY RAIN FROM A  
  THUNDERSTORM OVER THE WARNED AREA WITH MINOR FLOODING REPORTED.
  A THUNDERSTORM...APPROACHING FROM THE NORTHWEST WILL
  PRODUCE AN ADDITIONAL ONE TO TWO INCHES OF RAINFALL OVER A SHORT
  PERIOD OF TIME ACROSS THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  STERLINGTON...

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 3240 9199 3228 9203 3228 9210 3226 9211
      3228 9231 3232 9231 3241 9242 3258 9241
      3259 9223 3272 9207 3269 9204 3271 9204
      3271 9198 3266 9194 3266 9191 3259 9193
      3251 9190

$$

05

1 follow-up statement

188 
WGUS74 KSHV 171452
FFSSHV

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
952 AM CDT FRI AUG 17 2012

LAC073-171502-
/O.CAN.KSHV.FF.W.0033.000000T0000Z-120817T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
OUACHITA LA-
952 AM CDT FRI AUG 17 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR OUACHITA PARISH...

LAT...LON 3240 9199 3228 9203 3228 9210 3226 9211
      3228 9231 3232 9231 3241 9242 3258 9241
      3259 9223 3272 9207 3269 9204 3271 9204
      3271 9198 3266 9194 3266 9191 3259 9193
      3251 9190

$$

PARKER

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 6:45 AM CDT	Areal Flood Advisory	SHV	Bienville, Bossier, Caddo, De Soto, Webster	2 hr
Aug 17, 8:17 AM CDT	Severe Thunderstorm Warning	SHV	Ouachita	37 min
Aug 17, 8:26 AM CDT	Severe Thunderstorm Warning	SHV	Ouachita, Union	28 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.