Alert archive / Louisiana / Flash Flood Warnings in 2021

Flash Flood Warning 74, NWS New Orleans, LA

July 16, 2021Orleans Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Jul 16, 2021, 1:29 PM CDT for Orleans Parish, Louisiana. It was in force for 76 min. 1 report 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 16, 2021, 1:29 PM CDT (18:29 UTC)
Expired
Jul 16, 2021, 2:45 PM CDT
In force
76 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

County Orleans Parish, LA

What was reported inside it

TimeReportWhereRemark
Jul 16, 1:38 PM CDTFLASH FLOOD2 Nne New Orleans, LAHIGH WATER ON PARIS AVE UNDERPASS NEAR GENTILLY BLVD.

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 48 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, Slidell Radar S, LA at 12:00Z on 2021-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2218 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 12:00Z on 2021-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 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
2218 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
672 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
-1 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

083 
WGUS54 KLIX 161829
FFWLIX
LAC071-162130-
/O.NEW.KLIX.FF.W.0074.210716T1829Z-210716T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New Orleans LA
129 PM CDT Fri Jul 16 2021

The National Weather Service in New Orleans has issued a

* Flash Flood Warning for...
  Southwestern Orleans Parish in southeastern Louisiana...

* Until 430 PM CDT.

* At 129 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, Marrero, Jefferson, Gretna and Westwego.

This includes the following Interstates...
	Interstate 10 in Louisiana between mile markers 231 and 239.
	Interstate 610 between mile markers 1 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3004 9004 2992 9002 2992 9003 2995 9006
      2994 9006 2993 9006 2992 9007 2991 9011
      2991 9013 2992 9013 2995 9014 2997 9012
      3002 9012 3002 9011 3003 9011 3003 9009
      3003 9008

FLASH FLOOD...RADAR INDICATED

$$

MW
1 follow-up statement
907 
WGUS74 KLIX 161945
FFSLIX

Flash Flood Statement
National Weather Service New Orleans LA
245 PM CDT Fri Jul 16 2021

LAC071-161955-
/O.CAN.KLIX.FF.W.0074.000000T0000Z-210716T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Orleans LA-
245 PM CDT Fri Jul 16 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHWESTERN ORLEANS 
PARISH...

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

LAT...LON 3004 9004 2992 9002 2992 9003 2995 9006
      2994 9006 2993 9006 2992 9007 2991 9011
      2991 9013 2992 9013 2995 9014 2997 9012
      3002 9012 3002 9011 3003 9011 3003 9009
      3003 9008

$$

MW

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 1:13 PM CDTSpecial Weather StatementLIXOrleans32 min
Jul 16, 1:20 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines103 min
Jul 16, 1:45 PM CDTSpecial Weather StatementLIXOrleans30 min
Jul 16, 2:05 PM CDTSpecial Marine WarningLIX55 min
Jul 16, 2:14 PM CDTSpecial Marine WarningLIX61 min
Jul 16, 2:17 PM CDTSpecial Weather StatementLIXLafourche28 min
Jul 16, 2:32 PM CDTSpecial Weather StatementLIXSaint Charles28 min
Jul 16, 2:37 PM CDTSpecial Weather StatementLIXWashington23 min
Jul 16, 2:43 PM CDTSpecial Weather StatementLIXSaint James32 min
Jul 16, 2:48 PM CDTSpecial Weather StatementLIXLafourche27 min
Jul 16, 3:00 PM CDTSpecial Weather StatementLIXWashington30 min
Jul 16, 3:13 PM CDTSpecial Weather StatementLIXSaint James32 min
Jul 16, 3:17 PM CDTSpecial Weather StatementLIXIberville43 min
Jul 16, 3:24 PM CDTSpecial Weather StatementLIXWashington36 min
Jul 16, 3:31 PM CDTAreal Flood AdvisoryLIXSaint Tammany, Tangipahoa, Washington3 hr
Jul 16, 3:34 PM CDTSpecial Weather StatementLIXTangipahoa26 min
Jul 16, 3:38 PM CDTSpecial Weather StatementLIXSaint James37 min
Jul 16, 3:56 PM CDTSpecial Weather StatementLIXTangipahoa34 min
Jul 16, 4:01 PM CDTSpecial Weather StatementLIXEast Baton Rouge29 min
Jul 16, 4:06 PM CDTSpecial Weather StatementLIXJefferson24 min
Jul 16, 4:16 PM CDTAreal Flood AdvisoryLIXSaint Tammany, Tangipahoa, Washington3 hr
Jul 16, 4:28 PM CDTSpecial Weather StatementLIXEast Feliciana62 min
Jul 16, 4:35 PM CDTAreal Flood AdvisoryLIXAscension, East Baton Rouge, Livingston105 min
Jul 16, 5:16 PM CDTSpecial Weather StatementLIXSaint Helena44 min

Nearby

Flash Flood Warnings in Louisiana, 2021Every 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.