Alert archive / Louisiana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 46, NWS New Orleans, LA

April 10, 20216 parishes in Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Apr 10, 2021, 4:58 AM CDT for 6 parishes in Louisiana. It was in force for 47 min. 3 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
Apr 10, 2021, 4:58 AM CDT (09:58 UTC)
Expired
Apr 10, 2021, 5:45 AM CDT
In force
47 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Hail
0.75 in
Wind
70.0 mph

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

What was reported inside it

TimeReportWhereRemark
Apr 10, 5:01 AM CDTMARINE TSTM WIND 45Eden Isle, LAWEATHERFLOW SITE MEASURED A WIND GUST OF 45MPH.
Apr 10, 5:10 AM CDTTSTM WND DMG1 E Slidell, LAFIRE CHIEF REPORTS TREES AND POWERLINES DOWN ON THE EAST SIDE OF ST TAMMANY PARISH.
Apr 10, 5:10 AM CDTTSTM WND DMG1 E Slidell, LAFIRE DEPARTMENT REPORTS TREES AND POWERLINES DOWN ON THE EAST SIDE OF ST. TAMMANY PARISH.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 10, 12:16 AM CDTTornado WatchSPC7 hr

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 10.0 hours before the alert went out and 27 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 00:00Z on 2021-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2977 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 00:00Z on 2021-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 243 square meters per square second.193958Sfc1 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
2977 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
599 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
243 m²/s²
0-3 km storm-relative helicity
269 m²/s²
Significant tornado parameter
3.4
Supercell composite
18.1

Open this sounding in Storm Lab

The text

As transmitted.

156 
WUUS54 KLIX 100958
SVRLIX
LAC051-071-075-087-089-103-101045-
/O.NEW.KLIX.SV.W.0046.210410T0958Z-210410T1045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service New Orleans LA
458 AM CDT Sat Apr 10 2021

The National Weather Service in New Orleans has issued a

* Severe Thunderstorm Warning for...
  St. Bernard Parish in southeastern Louisiana...
  Eastern St. Charles Parish in southeastern Louisiana...
  Orleans Parish in southeastern Louisiana...
  Southeastern St. Tammany Parish in southeastern Louisiana...
  Northwestern Jefferson Parish in southeastern Louisiana...
  Northwestern Plaquemines Parish in southeastern Louisiana...

* Until 545 AM CDT.

* At 458 AM CDT, severe thunderstorms were located along a line
  extending from 8 miles north of New Orleans to 7 miles northwest of
  Metairie, moving southeast at 35 mph.

  HAZARD...70 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  New Orleans, Slidell, Chalmette, Avondale, Metairie, Marrero,
  Harvey, East New Orleans, Timberlane, Belle Chasse, Hahnville,
  Jefferson, Gretna, Harahan, Westwego, Jean Lafitte, Lake Catherine,
  Luling, Poydras and River Ridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 700 AM CDT for southeastern
Louisiana...and southern Mississippi.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3004 9045 3003 9003 3015 8988 3010 8981
      3018 8968 3026 8991 3033 8969 3016 8957
      3002 8972 3002 8984 2994 8984 2996 8973
      2987 8962 3004 8949 2985 8936 2969 9027
TIME...MOT...LOC 0958Z 321DEG 30KT 3019 8988 3008 9026 

HAIL...<.75IN
WIND...70MPH
 
$$

MEFFER
1 follow-up statement
587 
WWUS54 KLIX 101029
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
529 AM CDT Sat Apr 10 2021

LAC089-103-101039-
/O.CAN.KLIX.SV.W.0046.000000T0000Z-210410T1045Z/
St. Charles LA-St. Tammany LA-
529 AM CDT Sat Apr 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN ST. CHARLES AND
SOUTHEASTERN ST. TAMMANY PARISHES IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 2973 9008 3002 9012 3006 8997 3015 8988
      3010 8981 3017 8969 3015 8963 3007 8969
      3006 8973 3002 8972 3004 8982 3002 8984
      2994 8984 2993 8980 2996 8973 2992 8975
      2988 8972 2987 8962 3004 8949 2985 8936
TIME...MOT...LOC 1029Z 321DEG 36KT 2997 8968 2986 9006 

$$

LAC051-071-075-087-101045-
/O.CON.KLIX.SV.W.0046.000000T0000Z-210410T1045Z/
St. Bernard LA-Orleans LA-Jefferson LA-Plaquemines LA-
529 AM CDT Sat Apr 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 AM CDT
FOR ST. BERNARD...ORLEANS...NORTH CENTRAL JEFFERSON AND NORTHWESTERN
PLAQUEMINES PARISHES...

At 529 AM CDT, severe thunderstorms were located along a line
extending from 6 miles north of Shell Beach to Woodmere, moving
southeast at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
New Orleans, Chalmette, Harvey, East New Orleans, Timberlane, Belle
Chasse, Marrero, Gretna, Jean Lafitte, Lake Catherine, Woodmere,
Violet, Terrytown, Meraux, Poydras, Shell Beach, Arabi, Estelle and
Lakefront Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 2973 9008 3002 9012 3006 8997 3015 8988
      3010 8981 3017 8969 3015 8963 3007 8969
      3006 8973 3002 8972 3004 8982 3002 8984
      2994 8984 2993 8980 2996 8973 2992 8975
      2988 8972 2987 8962 3004 8949 2985 8936
TIME...MOT...LOC 1029Z 321DEG 36KT 2997 8968 2986 9006 

HAIL...<.75IN
WIND...60MPH
 
$$

MEFFER

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 10, 12:41 AM CDTSevere Thunderstorm WarningLIXSaint Tammany, Washington11 min
Apr 10, 1:07 AM CDTSpecial Marine WarningLIX22 min
Apr 10, 1:40 AM CDTSpecial Marine WarningLIX20 min
Apr 10, 1:45 AM CDTTornado WarningLIXPointe Coupee, West Feliciana45 min
Apr 10, 1:52 AM CDTSpecial Weather StatementLIXSaint Tammany38 min
Apr 10, 2:01 AM CDTSevere Thunderstorm WarningLIXSaint Tammany, Washington29 min
Apr 10, 2:05 AM CDTTornado WarningLIXSaint Tammany10 min
Apr 10, 2:28 AM CDTSevere Thunderstorm WarningLIXPointe Coupee, West Feliciana47 min
Apr 10, 2:48 AM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, East Feliciana, Saint Helena, West Feliciana39 min
Apr 10, 2:58 AM CDTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa35 min
Apr 10, 3:20 AM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, East Feliciana, Pointe Coupee, West Baton Rouge, West Feliciana33 min
Apr 10, 3:25 AM CDTSpecial Weather StatementLIXSaint Helena, Tangipahoa65 min
Apr 10, 3:26 AM CDTSpecial Weather StatementLIXAscension, Assumption, Livingston, Saint James, Saint John the Baptist64 min
Apr 10, 3:38 AM CDTSpecial Marine WarningLIX67 min
Apr 10, 3:59 AM CDTSpecial Weather StatementLIXEast Baton Rouge46 min
Apr 10, 4:16 AM CDTSpecial Marine WarningLIX59 min
Apr 10, 4:23 AM CDTTornado WarningLIXSaint James, Saint John the Baptist19 min
Apr 10, 4:40 AM CDTFlash Flood WarningLIXSaint Tammany, Tangipahoa, Washington3 hr
Apr 10, 4:47 AM CDTSpecial Weather StatementLIXAscension, Assumption, Orleans, Saint Charles, Saint James, Saint John the Baptist and 1 more58 min
Apr 10, 5:16 AM CDTFlash Flood WarningLIXOrleans3 hr
Apr 10, 5:23 AM CDTSpecial Marine WarningLIX67 min
Apr 10, 5:24 AM CDTFlash Flood WarningLIXSaint Bernard3 hr
Apr 10, 5:46 AM CDTSpecial Weather StatementLIXAssumption, Jefferson, Orleans, Saint Charles59 min
Apr 10, 6:07 AM CDTAreal Flood AdvisoryLIXJefferson, Lafourche, Orleans, Saint Charles, Saint John the Baptist, Terrebonne2 hr
Apr 10, 6:24 AM CDTSpecial Marine WarningLIX96 min
Apr 10, 6:29 AM CDTFlash Flood WarningLIXLafourche, Terrebonne89 min
Apr 10, 6:33 AM CDTFlash Flood WarningLIXJefferson, Plaquemines105 min
Apr 10, 6:42 AM CDTSpecial Weather StatementLIXJefferson, Lafourche, Plaquemines, Terrebonne78 min
Apr 10, 7:13 AM CDTSpecial Marine WarningLIX92 min
Apr 10, 7:53 AM CDTSpecial Marine WarningLIX97 min
Apr 10, 8:52 AM CDTRiver Flood WarningLIXSaint Tammany10 days
Apr 10, 8:52 AM CDTRiver Flood WarningLIXSaint Tammany24 hr
Apr 10, 8:55 AM CDTRiver Flood WarningLIXSaint Tammany25 hr
Apr 10, 9:49 AM CDTRiver Flood WarningLIXWashington33 hr
Apr 10, 11:15 AM CDTSpecial Weather StatementLIXTerrebonne30 min
Apr 10, 11:51 AM CDTSpecial Weather StatementLIXLafourche39 min
Apr 10, 12:28 PM CDTSpecial Weather StatementLIXJefferson32 min
Apr 10, 5:46 PM CDTRiver Flood WarningLIXSaint Helena26 hr

Nearby

Severe Thunderstorm Warnings in Louisiana, 2021Every severe thunderstorm 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.