Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 30, NWS Shreveport, LA

August 2, 2021Ouachita Parish, Louisiana

NWS Shreveport, LA issued this flash flood warning at Aug 2, 2021, 5:53 PM CDT for Ouachita Parish, Louisiana. It was in force for 3 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 2, 2021, 5:53 PM CDT (22:53 UTC)
Expired: Aug 2, 2021, 9:00 PM CDT
In force: 3 hr
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Flood severity: None

County Ouachita Parish, LA

The radar

The Shreveport radar (KSHV), 174 km from the middle of the area, began a volume at 22:54 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 10.9 hours before the alert went out and 166 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: 552 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 743 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 66 m²/s²
0-3 km storm-relative helicity: 98 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

As transmitted.

671 
WGUS54 KSHV 022253
FFWSHV
LAC073-030200-
/O.NEW.KSHV.FF.W.0030.210802T2253Z-210803T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
Issued by National Weather Service Fort Worth TX
553 PM CDT Mon Aug 2 2021

The National Weather Service in Shreveport has issued a

* Flash Flood Warning for...
  East Central Ouachita Parish in north central Louisiana...

* Until 900 PM CDT.

* At 553 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Monroe, West Monroe, Swartz, Brownsville-Bawcomville, Richwood, 
  Pine Grove and Millhaven.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3257 9211 3254 9192 3254 9191 3252 9190
      3251 9191 3250 9192 3249 9193 3246 9194
      3246 9195 3245 9194 3245 9195 3243 9196
      3242 9198 3241 9198 3240 9199 3249 9216
      3253 9215

FLASH FLOOD...RADAR INDICATED

$$

1 follow-up statement

312 
WGUS74 KSHV 030156
FFSSHV

Flash Flood Statement
National Weather Service Shreveport LA
856 PM CDT Mon Aug 2 2021

LAC073-030206-
/O.EXP.KSHV.FF.W.0030.000000T0000Z-210803T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ouachita LA-
856 PM CDT Mon Aug 2 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 9 PM CDT THIS EVENING FOR EAST 
CENTRAL OUACHITA PARISH...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

LAT...LON 3257 9211 3254 9192 3254 9191 3252 9190
      3251 9191 3250 9192 3249 9193 3246 9194
      3246 9195 3245 9194 3245 9195 3243 9196
      3242 9198 3240 9198 3240 9199 3249 9216
      3253 9215

$$

33

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 1, 7:15 PM CDT	Special Weather Statement	SHV	Union	30 min
Aug 1, 8:09 PM CDT	Areal Flood Advisory	SHV	Ouachita, Union	111 min
Aug 1, 8:16 PM CDT	Special Weather Statement	SHV	Union	29 min
Aug 1, 9:09 PM CDT	Special Weather Statement	SHV	Lincoln	36 min
Aug 1, 9:20 PM CDT	Special Weather Statement	SHV	Webster	40 min
Aug 1, 10:02 PM CDT	Special Weather Statement	SHV	Webster	43 min
Aug 1, 10:31 PM CDT	Special Weather Statement	SHV	Claiborne	44 min
Aug 2, 4:52 AM CDT	Areal Flood Advisory	SHV	Ouachita	3 hr
Aug 2, 6:38 PM CDT	Areal Flood Advisory	SHV	Claiborne, Lincoln, Union	3 hr

Nearby

Flash Flood Warnings in Louisiana, 2021 Every flash flood warning in 2021

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; radar from the NEXRAD Level II archive.