Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 82, NWS New Orleans, LA

August 3, 2021Saint James Parish, Saint John the Baptist Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 3, 2021, 4:53 PM CDT for Saint James Parish, Saint John the Baptist Parish, Louisiana. It was in force for 39 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 3, 2021, 4:53 PM CDT (21:53 UTC)
Expired: Aug 3, 2021, 5:32 PM CDT
In force: 39 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Flood severity: None

Counties Saint James Parish, LA, Saint John the Baptist Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 9.9 hours before the alert went out and 97 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: 928 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 708 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 72 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

347 
WGUS54 KLIX 032153
FFWLIX
LAC093-095-040100-
/O.NEW.KLIX.FF.W.0082.210803T2153Z-210804T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
453 PM CDT Tue Aug 3 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  East Central St. James Parish in southeastern Louisiana...
  West Central St. John The Baptist Parish in southeastern Louisiana...

* Until 800 PM CDT.

* At 453 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 4.5 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...
  Reserve, Gramercy, Lutcher, Wallace, North Vacherie, Garyville and 
  Edgard.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

Stay away or be swept away. River banks and culverts can become 
unstable and unsafe.

&&

LAT...LON 3007 9072 3007 9059 3002 9058 2999 9062
      2996 9073 3001 9074

FLASH FLOOD...RADAR INDICATED

$$

CAB

1 follow-up statement

662 
WGUS74 KLIX 032232
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
532 PM CDT Tue Aug 3 2021

LAC093-095-032242-
/O.CAN.KLIX.FF.W.0082.000000T0000Z-210804T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
St. James LA-St. John The Baptist LA-
532 PM CDT Tue Aug 3 2021

...FLASH FLOOD WARNING IS CANCELLED FOR EAST CENTRAL ST. JAMES AND 
WEST CENTRAL ST. JOHN THE BAPTIST PARISHES...

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

LAT...LON 3007 9072 3007 9059 3002 9058 2999 9062
      2996 9073 3001 9074

$$

CAB

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 3, 4:23 AM CDT	Special Marine Warning	LIX		67 min
Aug 3, 6:33 AM CDT	Special Weather Statement	LIX	Plaquemines	27 min
Aug 3, 6:44 AM CDT	Special Weather Statement	LIX	Ascension, Lafourche, Saint James	61 min
Aug 3, 7:47 AM CDT	Special Weather Statement	LIX	Saint Charles, Saint John the Baptist	88 min
Aug 3, 8:42 AM CDT	Special Marine Warning	LIX		63 min
Aug 3, 8:50 AM CDT	Areal Flood Advisory	LIX	Orleans, Saint Bernard	19 min
Aug 3, 9:09 AM CDT	Flash Flood Warning	LIX	Orleans	2 hr
Aug 3, 10:04 AM CDT	Special Marine Warning	LIX		86 min
Aug 3, 10:24 AM CDT	Special Marine Warning	LIX		96 min
Aug 3, 10:40 AM CDT	Areal Flood Advisory	LIX	Ascension, East Baton Rouge, Livingston	90 min
Aug 3, 10:53 AM CDT	Areal Flood Advisory	LIX	Ascension, East Baton Rouge, Livingston	77 min
Aug 3, 11:04 AM CDT	Special Marine Warning	LIX		116 min
Aug 3, 11:40 AM CDT	Special Marine Warning	LIX		110 min
Aug 3, 11:49 AM CDT	Special Marine Warning	LIX		86 min
Aug 3, 11:52 AM CDT	Special Marine Warning	LIX		113 min
Aug 3, 2:45 PM CDT	Flash Flood Warning	LIX	East Baton Rouge, Livingston	4 hr
Aug 3, 3:00 PM CDT	Areal Flood Advisory	LIX	Jefferson, Orleans, Saint Charles, Saint John the Baptist	3 hr
Aug 3, 3:28 PM CDT	Flash Flood Warning	LIX	Saint Charles, Saint John the Baptist	2 hr
Aug 3, 3:39 PM CDT	Areal Flood Advisory	LIX	Jefferson, Orleans, Plaquemines, Saint Bernard	119 min
Aug 3, 3:52 PM CDT	Areal Flood Advisory	LIX	Ascension, Saint Charles, Saint James, Saint John the Baptist	103 min
Aug 3, 4:39 PM CDT	Areal Flood Advisory	LIX	Saint Charles, Saint James, Saint John the Baptist	50 min
Aug 3, 5:27 PM CDT	Areal Flood Advisory	LIX	Saint Tammany, Tangipahoa, Washington	3 hr
Aug 3, 5:33 PM CDT	Areal Flood Advisory	LIX	Saint Tammany	117 min

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.