Alert archive / Louisiana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 150, NWS New Orleans, LA

December 6, 2021Livingston Parish, Saint Helena Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Dec 6, 2021, 1:44 PM CST for Livingston Parish, Saint Helena Parish, Louisiana. It was in force for 61 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
Dec 6, 2021, 1:44 PM CST (19:44 UTC)
Expired
Dec 6, 2021, 2:45 PM CST
In force
61 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

Counties Livingston Parish, LA, Saint Helena Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 7.7 hours before the alert went out and 113 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 2021-12-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 720 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 2021-12-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 180 square meters per square second.1939587897Sfc1 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
720 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
680 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
180 m²/s²
0-3 km storm-relative helicity
201 m²/s²
Significant tornado parameter
0.5
Supercell composite
5.4

Open this sounding in Storm Lab

The text

As transmitted.

016 
WUUS54 KLIX 061944
SVRLIX
LAC063-091-062045-
/O.NEW.KLIX.SV.W.0150.211206T1944Z-211206T2045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service New Orleans LA
144 PM CST Mon Dec 6 2021

The National Weather Service in New Orleans has issued a

* Severe Thunderstorm Warning for...
  Southern St. Helena Parish in southeastern Louisiana...
  Northeastern Livingston Parish in southeastern Louisiana...

* Until 245 PM CST.

* At 143 PM CST, a severe thunderstorm was located 7 miles east of
  Pride, or 15 miles southwest of Greensburg, moving east at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Montpelier.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3054 9057 3063 9093 3067 9089 3070 9085
      3072 9084 3074 9085 3076 9084 3076 9057
TIME...MOT...LOC 1943Z 278DEG 20KT 3068 9086 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

CAB
1 follow-up statement
373 
WWUS54 KLIX 062009
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
209 PM CST Mon Dec 6 2021

LAC063-091-062045-
/O.CON.KLIX.SV.W.0150.000000T0000Z-211206T2045Z/
St. Helena LA-Livingston LA-
209 PM CST Mon Dec 6 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 PM CST
FOR SOUTHEASTERN ST. HELENA AND NORTHEASTERN LIVINGSTON PARISHES...

At 209 PM CST, a severe thunderstorm was located over Montpelier, or
11 miles south of Greensburg, moving east at 25 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Montpelier.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3054 9057 3059 9076 3069 9071 3076 9057
TIME...MOT...LOC 2009Z 278DEG 20KT 3066 9069 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

CAB

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 6, 11:08 AM CSTSpecial Weather StatementLIXEast Feliciana67 min
Dec 6, 12:01 PM CSTSpecial Weather StatementLIXSaint Helena74 min
Dec 6, 12:21 PM CSTSevere Thunderstorm WarningLIXEast Feliciana, Saint Helena54 min
Dec 6, 12:46 PM CSTSevere Thunderstorm WarningLIXTangipahoa, Washington59 min
Dec 6, 1:22 PM CSTTornado WarningLIXTangipahoa, Washington68 min
Dec 6, 1:29 PM CSTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa, Washington61 min
Dec 6, 1:40 PM CSTSpecial Weather StatementLIXSaint Helena65 min
Dec 6, 1:54 PM CSTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa66 min
Dec 6, 2:21 PM CSTSevere Thunderstorm WarningLIXSaint Tammany, Washington39 min
Dec 6, 2:24 PM CSTTornado WarningLIXWashington21 min
Dec 6, 2:30 PM CSTSevere Thunderstorm WarningLIXLivingston, Saint Tammany, Tangipahoa60 min
Dec 6, 2:35 PM CSTTornado WarningLIXSaint Tammany, Washington55 min
Dec 6, 2:41 PM CSTSpecial Marine WarningLIX64 min
Dec 6, 2:51 PM CSTFlash Flood WarningLIXAscension, East Baton Rouge, West Baton Rouge116 min
Dec 6, 2:51 PM CSTTornado WarningLIXSaint Tammany39 min
Dec 6, 2:56 PM CSTTornado WarningLIXSaint Tammany49 min
Dec 6, 3:09 PM CSTSevere Thunderstorm Warning Considerable damage threatLIXSaint Tammany66 min
Dec 6, 3:20 PM CSTTornado WarningLIXSaint Tammany30 min
Dec 6, 3:26 PM CSTSpecial Marine WarningLIX64 min
Dec 6, 4:14 PM CSTSpecial Marine WarningLIX91 min
Dec 6, 5:24 PM CSTSpecial Marine WarningLIX66 min

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; the sounding from the Mesonet's radiosonde archive.