Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 65, NWS New Orleans, LA

July 3, 20214 parishes in Louisiana

NWS New Orleans, LA issued this flash flood warning at Jul 3, 2021, 1:31 PM CDT for 4 parishes in Louisiana. It was in force for 111 min. 2 reports 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: Jul 3, 2021, 1:31 PM CDT (18:31 UTC)
Expired: Jul 3, 2021, 3:22 PM CDT
In force: 111 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Flood severity: None

Counties Jefferson Parish, LA, Orleans Parish, LA, Plaquemines Parish, LA, Saint Bernard Parish, LA

What was reported inside it

Time	Report	Where	Remark
Jul 3, 2:20 PM CDT	FLASH FLOOD	2 Wnw Chalmette, LA	NWS EMPLOYEE REPORTS MULTIPLE FLOODED STREETS WITH ONE WITH ITS SIDEWALK COVERED. MEASURED 4 INCHES OF RAIN AS OF APPROXIMATELY 2:20 PM.
Jul 3, 2:30 PM CDT	FLASH FLOOD	4 Wnw Chalmette, LA	VIDEO ON SOCIAL MEDIA SHOWS FLOODED STREET IN LOWER NINTH WARD. WATER HAS GOTTEN UP TO ALMOST THE BUMPER OF A CAR.

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, 6.5 hours before the alert went out and 44 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: 1029 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 609 m above ground
0-6 km bulk shear: 4 kt
0-1 km storm-relative helicity: -50 m²/s²
0-3 km storm-relative helicity: -48 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

589 
WGUS54 KLIX 031831
FFWLIX
LAC051-071-075-087-032130-
/O.NEW.KLIX.FF.W.0065.210703T1831Z-210703T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
131 PM CDT Sat Jul 3 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  Northeastern Jefferson Parish in southeastern Louisiana...
  Southwestern Orleans Parish in southeastern Louisiana...
  Northwestern Plaquemines Parish in southeastern Louisiana...
  West Central St. Bernard Parish in southeastern Louisiana...

* Until 430 PM CDT.

* At 131 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 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...
  New Orleans, Chalmette, Timberlane, Belle Chasse, Gretna, Meraux, 
  Arabi, Violet and Terrytown.

This includes the following Interstates...
	Interstate 10 in Louisiana near mile marker 238.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2999 9006 3000 8990 2989 8982 2988 9002
      2992 9004

FLASH FLOOD...RADAR INDICATED

$$

MW

1 follow-up statement

147 
WGUS74 KLIX 032022
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
322 PM CDT Sat Jul 3 2021

LAC051-071-075-087-032032-
/O.CAN.KLIX.FF.W.0065.000000T0000Z-210703T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson LA-Orleans LA-Plaquemines LA-St. Bernard LA-
322 PM CDT Sat Jul 3 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN JEFFERSON, 
SOUTHWESTERN ORLEANS, NORTHWESTERN PLAQUEMINES AND WEST CENTRAL ST. 
BERNARD PARISHES...

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 2999 9006 3000 8990 2989 8982 2988 9002
      2992 9004

$$

MW

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 2, 7:15 PM CDT	Flash Flood Warning	LIX	Ascension, East Baton Rouge	3 hr
Jul 2, 7:48 PM CDT	Special Marine Warning	LIX		57 min
Jul 2, 7:56 PM CDT	Special Weather Statement	LIX	Saint Charles, Saint John the Baptist	34 min
Jul 2, 8:14 PM CDT	Areal Flood Advisory	LIX	East Baton Rouge	61 min
Jul 2, 8:56 PM CDT	Special Marine Warning	LIX		64 min
Jul 2, 9:52 PM CDT	Special Marine Warning	LIX		38 min
Jul 3, 1:23 PM CDT	Areal Flood Advisory	LIX	Jefferson, Orleans, Plaquemines, Saint Bernard, Saint Charles	3 hr
Jul 3, 1:48 PM CDT	Areal Flood Advisory	LIX	Ascension, East Baton Rouge, Iberville, Livingston	44 min
Jul 3, 2:25 PM CDT	Flash Flood Warning	LIX	Jefferson, Orleans	3 hr
Jul 3, 3:02 PM CDT	Flash Flood Warning	LIX	Jefferson	3 hr
Jul 3, 4:39 PM CDT	Special Weather Statement	LIX	East Baton Rouge	36 min
Jul 3, 4:58 PM CDT	Special Weather Statement	LIX	East Baton Rouge	32 min
Jul 3, 5:10 PM CDT	Areal Flood Advisory	LIX	Ascension, East Baton Rouge, Iberville, Livingston, West Baton Rouge	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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.