Alert archive / Louisiana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 149, NWS New Orleans, LA

December 6, 2021Saint Helena Parish, Tangipahoa Parish, Washington Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Dec 6, 2021, 1:29 PM CST for Saint Helena Parish, Tangipahoa Parish, Washington 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, 1:29 PM CST (19:29 UTC)
Expired: Dec 6, 2021, 2:30 PM CST
In force: 61 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Saint Helena Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 7.5 hours before the alert went out and 94 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: 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.

843 
WUUS54 KLIX 061929
SVRLIX
LAC091-105-117-062030-
/O.NEW.KLIX.SV.W.0149.211206T1929Z-211206T2030Z/

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

The National Weather Service in New Orleans has issued a

* Severe Thunderstorm Warning for...
  East central St. Helena Parish in southeastern Louisiana...
  Northern Tangipahoa Parish in southeastern Louisiana...
  West central Washington Parish in southeastern Louisiana...

* Until 230 PM CST.

* At 129 PM CST, a severe thunderstorm was located near Roseland, or
  near Greensburg, moving east at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Amite, Amite City, Roseland and Wilmer. 

This includes Interstate 55 in Louisiana between mile markers 47 and
56.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3077 9065 3087 9057 3082 9019 3063 9031
TIME...MOT...LOC 1929Z 279DEG 20KT 3079 9058 

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

$$

CAB

1 follow-up statement

108 
WWUS54 KLIX 061938
SVSLIX

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

LAC091-061947-
/O.CAN.KLIX.SV.W.0149.000000T0000Z-211206T2030Z/
St. Helena LA-
138 PM CST Mon Dec 6 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL ST. HELENA PARISH
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3076 9057 3085 9053 3082 9019 3063 9031
TIME...MOT...LOC 1937Z 279DEG 20KT 3078 9052 

$$

LAC105-117-062030-
/O.CON.KLIX.SV.W.0149.000000T0000Z-211206T2030Z/
Tangipahoa LA-Washington LA-
138 PM CST Mon Dec 6 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 PM CST
FOR NORTHERN TANGIPAHOA AND WEST CENTRAL WASHINGTON PARISHES...

At 137 PM CST, a severe thunderstorm was located over Roseland, or
near Amite, moving east at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Amite, Amite City, Roseland and Wilmer. 

This includes Interstate 55 in Louisiana between mile markers 49 and
55.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3076 9057 3085 9053 3082 9019 3063 9031
TIME...MOT...LOC 1937Z 279DEG 20KT 3078 9052 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 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.

Issued	Product	Office	Counties	Lasted
Dec 6, 11:08 AM CST	Special Weather Statement	LIX	East Feliciana	67 min
Dec 6, 12:01 PM CST	Special Weather Statement	LIX	Saint Helena	74 min
Dec 6, 12:21 PM CST	Severe Thunderstorm Warning	LIX	East Feliciana, Saint Helena	54 min
Dec 6, 12:46 PM CST	Severe Thunderstorm Warning	LIX	Tangipahoa, Washington	59 min
Dec 6, 1:22 PM CST	Tornado Warning	LIX	Tangipahoa, Washington	68 min
Dec 6, 1:40 PM CST	Special Weather Statement	LIX	Saint Helena	65 min
Dec 6, 1:44 PM CST	Severe Thunderstorm Warning	LIX	Livingston, Saint Helena	61 min
Dec 6, 1:54 PM CST	Severe Thunderstorm Warning	LIX	Saint Helena, Tangipahoa	66 min
Dec 6, 2:21 PM CST	Severe Thunderstorm Warning	LIX	Saint Tammany, Washington	39 min
Dec 6, 2:24 PM CST	Tornado Warning	LIX	Washington	21 min
Dec 6, 2:30 PM CST	Severe Thunderstorm Warning	LIX	Livingston, Saint Tammany, Tangipahoa	60 min
Dec 6, 2:35 PM CST	Tornado Warning	LIX	Saint Tammany, Washington	55 min
Dec 6, 2:41 PM CST	Special Marine Warning	LIX		64 min
Dec 6, 2:51 PM CST	Flash Flood Warning	LIX	Ascension, East Baton Rouge, West Baton Rouge	116 min
Dec 6, 2:51 PM CST	Tornado Warning	LIX	Saint Tammany	39 min
Dec 6, 2:56 PM CST	Tornado Warning	LIX	Saint Tammany	49 min
Dec 6, 3:09 PM CST	Severe Thunderstorm Warning Considerable damage threat	LIX	Saint Tammany	66 min
Dec 6, 3:20 PM CST	Tornado Warning	LIX	Saint Tammany	30 min
Dec 6, 3:26 PM CST	Special Marine Warning	LIX		64 min
Dec 6, 4:14 PM CST	Special Marine Warning	LIX		91 min
Dec 6, 5:24 PM CST	Special Marine Warning	LIX		66 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2021 Every 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.