Alert archive / Louisiana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 145, NWS New Orleans, LA

October 27, 20215 parishes in Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Oct 27, 2021, 6:49 PM CDT for 5 parishes in Louisiana. It was in force for 41 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
Oct 27, 2021, 6:49 PM CDT (23:49 UTC)
Expired
Oct 27, 2021, 7:30 PM CDT
In force
41 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

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

What was reported inside it

TimeReportWhereRemark
Oct 27, 6:51 PM CDTTSTM WND DMG1 Ene Belle Chasse, LAPUBLIC OBSERVES THUNDERSTORM WIND CAUSING LARGE TREE LIMB TO FALL IN FRONT OF VEHICLE.

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
Oct 27, 1:53 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 11.8 hours before the alert went out and 67 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 2021-10-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-10-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 186 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1792 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
186 m²/s²
0-3 km storm-relative helicity
274 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

243 
WUUS54 KLIX 272349
SVRLIX
LAC051-057-071-075-087-280030-
/O.NEW.KLIX.SV.W.0145.211027T2349Z-211028T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service New Orleans LA
649 PM CDT Wed Oct 27 2021

The National Weather Service in New Orleans has issued a

* Severe Thunderstorm Warning for...
  Western St. Bernard Parish in southeastern Louisiana...
  Orleans Parish in southeastern Louisiana...
  East central Lafourche Parish in southeastern Louisiana...
  Central Jefferson Parish in southeastern Louisiana...
  Plaquemines Parish in southeastern Louisiana...

* Until 730 PM CDT.

* At 648 PM CDT, severe thunderstorms were located along a line
  extending from Gretna to 7 miles north of Myrtle Grove to 10 miles
  east of Golden Meadow, moving northeast at 35 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  New Orleans, Chalmette, Marrero, Harvey, East New Orleans,
  Timberlane, Belle Chasse, Port Sulphur, Gretna, Westwego, Woodmere,
  Violet, Terrytown, Meraux, Empire, Poydras, Myrtle Grove, Pointe A
  La Hache, Estelle and Shell Beach.

This includes the following Interstates...
 Interstate 10 in Louisiana between mile markers 235 and 254.
 Interstate 510 between mile markers 1 and 3.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Squall lines can produce brief tornadoes and straight-line wind 
damage. Although a tornado is not immediately likely, it is best to 
move to an interior room on the lowest floor of a building. These 
storms may cause serious injury and significant property damage.

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

A Tornado Watch remains in effect until 1000 PM CDT for southeastern
Louisiana.

&&

LAT...LON 2930 8990 2949 8989 2937 9005 2929 8993
      2929 8994 2940 9027 2975 9006 2990 9015
      3015 8988 3015 8987 3008 8968 3000 8985
      2987 8970 3000 8949 2972 8960 2975 8965
      2964 8951 2961 8973 2946 8955 2927 8965
TIME...MOT...LOC 2348Z 231DEG 32KT 2990 9006 2975 8992 2938 9010 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JRK
2 follow-up statements
966 
WWUS54 KLIX 280024
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
724 PM CDT Wed Oct 27 2021

LAC051-057-071-280033-
/O.CAN.KLIX.SV.W.0145.000000T0000Z-211028T0030Z/
Orleans LA-Lafourche LA-Jefferson LA-
724 PM CDT Wed Oct 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR ORLEANS...EAST CENTRAL
LAFOURCHE AND CENTRAL JEFFERSON PARISHES IS CANCELLED...

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

A Tornado Watch remains in effect until 1000 PM CDT for southeastern
Louisiana.

LAT...LON 2934 8961 2962 8977 2989 8979 2992 8975
      2987 8970 3000 8949 2972 8960 2975 8965
      2964 8951 2961 8973 2946 8955
TIME...MOT...LOC 0023Z 255DEG 41KT 2989 8970 2974 8956 2932 8953 

$$

LAC075-087-280030-
/O.CON.KLIX.SV.W.0145.000000T0000Z-211028T0030Z/
St. Bernard LA-Plaquemines LA-
724 PM CDT Wed Oct 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM CDT
FOR CENTRAL ST. BERNARD AND NORTH CENTRAL PLAQUEMINES PARISHES...

At 723 PM CDT, severe thunderstorms were located along a line
extending from near Shell Beach to 18 miles northeast of Pointe A La
Hache to near Buras, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Port Sulphur, Empire and Shell Beach. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1000 PM CDT for southeastern
Louisiana.

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

&&

LAT...LON 2934 8961 2962 8977 2989 8979 2992 8975
      2987 8970 3000 8949 2972 8960 2975 8965
      2964 8951 2961 8973 2946 8955
TIME...MOT...LOC 0023Z 255DEG 41KT 2989 8970 2974 8956 2932 8953 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JRK
419 
WWUS54 KLIX 280026
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
726 PM CDT Wed Oct 27 2021

LAC075-087-280035-
/O.EXP.KLIX.SV.W.0145.000000T0000Z-211028T0030Z/
St. Bernard LA-Plaquemines LA-
726 PM CDT Wed Oct 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL ST. BERNARD AND NORTH
CENTRAL PLAQUEMINES PARISHES WILL EXPIRE AT 730 PM CDT...
    
The storms which prompted the warning have weakened below severe 
limits and have exited the warned area. Therefore, the warning will 
be allowed to expire.

A Tornado Watch remains in effect until 1000 PM CDT for southeastern
Louisiana.

LAT...LON 2934 8961 2962 8977 2989 8979 2992 8975
      2987 8970 3000 8949 2972 8960 2975 8965
      2964 8951 2961 8973 2946 8955
TIME...MOT...LOC 0025Z 231DEG 32KT 2989 8970 2974 8956 2932 8953 

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 27, 1:47 PM CDTTornado WarningLIXEast Baton Rouge, East Feliciana43 min
Oct 27, 1:48 PM CDTTornado WarningLIXEast Feliciana, West Feliciana42 min
Oct 27, 1:51 PM CDTSpecial Marine WarningLIX41 min
Oct 27, 2:03 PM CDTTornado WarningLIXLivingston, Tangipahoa42 min
Oct 27, 2:16 PM CDTSevere Thunderstorm WarningLIXIberville, Pointe Coupee, West Feliciana59 min
Oct 27, 3:10 PM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, East Feliciana, Iberville, Pointe Coupee, West Baton Rouge, West Feliciana50 min
Oct 27, 3:17 PM CDTSpecial Marine WarningLIX28 min
Oct 27, 3:19 PM CDTTornado WarningLIXEast Feliciana, West Feliciana26 min
Oct 27, 3:22 PM CDTSpecial Marine WarningLIX53 min
Oct 27, 3:56 PM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, East Feliciana, Iberville, Livingston, Saint Helena, West Baton Rouge49 min
Oct 27, 4:06 PM CDTSevere Thunderstorm WarningLIXAscension, Assumption, East Baton Rouge, Iberville, Livingston, Saint James and 1 more39 min
Oct 27, 4:46 PM CDTSevere Thunderstorm WarningLIXAscension, Assumption, East Baton Rouge, Iberville, Lafourche, Livingston and 4 more44 min
Oct 27, 4:54 PM CDTAreal Flood AdvisoryLIXLivingston, Saint Tammany, Tangipahoa, Washington3 hr
Oct 27, 4:59 PM CDTSpecial Marine WarningLIX91 min
Oct 27, 5:19 PM CDTSevere Thunderstorm WarningLIXSaint Tammany, Washington26 min
Oct 27, 5:22 PM CDTSevere Thunderstorm WarningLIXAscension, Assumption, Lafourche, Livingston, Saint Charles, Saint James and 2 more38 min
Oct 27, 5:26 PM CDTSpecial Marine WarningLIX94 min
Oct 27, 5:28 PM CDTFlash Flood WarningLIXSaint Tammany, Tangipahoa, Washington3 hr
Oct 27, 5:56 PM CDTSevere Thunderstorm WarningLIXJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 2 more49 min
Oct 27, 6:10 PM CDTSevere Thunderstorm WarningLIXSaint Tammany50 min
Oct 27, 6:19 PM CDTFlash Flood WarningLIXSaint Tammany, Washington2 hr
Oct 27, 6:23 PM CDTSpecial Marine WarningLIX97 min
Oct 27, 6:28 PM CDTTornado WarningLIXJefferson, Lafourche32 min
Oct 27, 6:37 PM CDTSpecial Marine WarningLIX83 min
Oct 27, 6:47 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Saint Bernard, Saint Charles109 min
Oct 27, 6:53 PM CDTAreal Flood AdvisoryLIXSaint Tammany3 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.