Alert archive / Louisiana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 73, NWS New Orleans, LA

April 15, 20214 parishes in Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Apr 15, 2021, 6:28 AM CDT for 4 parishes in Louisiana. It was in force for 18 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: Apr 15, 2021, 6:28 AM CDT (11:28 UTC)
Expired: Apr 15, 2021, 6:46 AM CDT
In force: 18 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Ascension Parish, LA, Saint Charles Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 11.5 hours before the alert went out and 82 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: 5 J/kg
Mixed-layer CIN: -620 J/kg
Mixed-layer LCL: 709 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 311 m²/s²
0-3 km storm-relative helicity: 272 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

401 
WUUS54 KLIX 151128
SVRLIX
LAC005-089-093-095-151200-
/O.NEW.KLIX.SV.W.0073.210415T1128Z-210415T1200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service New Orleans LA
628 AM CDT Thu Apr 15 2021

The National Weather Service in New Orleans has issued a

* Severe Thunderstorm Warning for...
  Central St. John The Baptist Parish in southeastern Louisiana...
  East central Ascension Parish in southeastern Louisiana...
  Northeastern St. James Parish in southeastern Louisiana...
  Northwestern St. Charles Parish in southeastern Louisiana...

* Until 700 AM CDT.

* At 627 AM CDT, a severe thunderstorm was located near Gramercy, or
  8 miles northwest of Reserve, moving east at 40 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Reserve, Laplace, Hahnville, Gramercy, Lutcher, Killona, Norco,
  Montz, Edgard, Garyville, New Sarpy, St. Rose, Taft, Wallace,
  Destrehan and Ama.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in New Orleans.

&&

LAT...LON 3019 9075 3019 9072 3017 9069 3019 9067
      3020 9060 3017 9057 3017 9050 3020 9045
      3020 9041 3018 9043 3011 9043 3006 9037
      3005 9028 2995 9028 3006 9077
TIME...MOT...LOC 1127Z 276DEG 35KT 3013 9068 

HAIL...0.75IN
WIND...60MPH
 
$$

PG

2 follow-up statements

469 
WWUS54 KLIX 151136
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
636 AM CDT Thu Apr 15 2021

LAC005-093-151145-
/O.CAN.KLIX.SV.W.0073.000000T0000Z-210415T1200Z/
Ascension LA-St. James LA-
636 AM CDT Thu Apr 15 2021

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

LAT...LON 3005 9066 3009 9067 3010 9065 3020 9063
      3020 9060 3017 9057 3017 9050 3020 9045
      3020 9042 3011 9043 3006 9037 3005 9028
      2995 9028 3004 9068
TIME...MOT...LOC 1135Z 276DEG 35KT 3012 9058 

$$

LAC089-095-151200-
/O.CON.KLIX.SV.W.0073.000000T0000Z-210415T1200Z/
St. John The Baptist LA-St. Charles LA-
636 AM CDT Thu Apr 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 AM CDT
FOR CENTRAL ST. JOHN THE BAPTIST AND NORTHWESTERN ST. CHARLES
PARISHES...

At 635 AM CDT, a severe thunderstorm was located near Reserve, moving
east at 40 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Reserve, Laplace, Hahnville, Killona, Norco, Montz, Edgard,
Garyville, New Sarpy, St. Rose, Taft, Wallace, Destrehan and Ama.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
New Orleans.

&&

LAT...LON 3005 9066 3009 9067 3010 9065 3020 9063
      3020 9060 3017 9057 3017 9050 3020 9045
      3020 9042 3011 9043 3006 9037 3005 9028
      2995 9028 3004 9068
TIME...MOT...LOC 1135Z 276DEG 35KT 3012 9058 

HAIL...0.75IN
WIND...60MPH
 
$$

PG

824 
WWUS54 KLIX 151146
SVSLIX

Severe Weather Statement
National Weather Service New Orleans LA
646 AM CDT Thu Apr 15 2021

LAC089-095-151156-
/O.CAN.KLIX.SV.W.0073.000000T0000Z-210415T1200Z/
St. John The Baptist LA-St. Charles LA-
646 AM CDT Thu Apr 15 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL ST. JOHN THE BAPTIST
AND NORTHWESTERN ST. CHARLES PARISHES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However gusty winds and
heavy rain are still possible with this thunderstorm.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
New Orleans.

LAT...LON 3005 9066 3009 9067 3010 9065 3020 9063
      3020 9060 3017 9057 3017 9050 3020 9045
      3020 9042 3011 9043 3006 9037 3005 9028
      2995 9028 3004 9068
TIME...MOT...LOC 1144Z 276DEG 35KT 3011 9050 

$$

PG

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 14, 7:57 PM CDT	Special Weather Statement	LIX	Plaquemines	63 min
Apr 14, 8:00 PM CDT	Special Marine Warning	LIX		2 hr
Apr 14, 8:22 PM CDT	Special Marine Warning	LIX		113 min
Apr 14, 9:12 PM CDT	River Flood Warning	LIX	East Baton Rouge	72 hr
Apr 14, 9:18 PM CDT	River Flood Warning	LIX	Saint Helena	62 hr
Apr 14, 9:18 PM CDT	River Flood Warning	LIX	Saint Helena	70 hr
Apr 14, 9:18 PM CDT	River Flood Warning	LIX	Livingston	4 days
Apr 14, 9:36 PM CDT	Special Marine Warning	LIX		84 min
Apr 14, 11:04 PM CDT	Areal Flood Advisory	LIX	Orleans, Saint Tammany	3 hr
Apr 14, 11:06 PM CDT	Special Marine Warning	LIX		84 min
Apr 14, 11:22 PM CDT	Special Weather Statement	LIX	Tangipahoa	53 min
Apr 14, 11:36 PM CDT	Areal Flood Advisory	LIX	Saint Tammany, Tangipahoa	3 hr
Apr 15, 12:10 AM CDT	Flash Flood Warning	LIX	Saint Tammany	2 hr
Apr 15, 12:15 AM CDT	Special Marine Warning	LIX		60 min
Apr 15, 12:24 AM CDT	Special Weather Statement	LIX	Saint Tammany	81 min
Apr 15, 12:33 AM CDT	Severe Thunderstorm Warning	LIX	Saint Tammany	57 min
Apr 15, 12:49 AM CDT	Flash Flood Warning	LIX	Saint Tammany	106 min
Apr 15, 1:03 AM CDT	Special Marine Warning	LIX		87 min
Apr 15, 1:07 AM CDT	Special Marine Warning	LIX		98 min
Apr 15, 1:38 AM CDT	Special Marine Warning	LIX		97 min
Apr 15, 2:01 AM CDT	Special Weather Statement	LIX	Saint Helena	44 min
Apr 15, 2:03 AM CDT	Special Weather Statement	LIX	Washington	57 min
Apr 15, 2:27 AM CDT	Special Marine Warning	LIX		33 min
Apr 15, 2:38 AM CDT	Severe Thunderstorm Warning	LIX	Saint Helena, Tangipahoa, Washington	27 min
Apr 15, 3:23 AM CDT	Special Marine Warning	LIX		22 min
Apr 15, 3:50 AM CDT	Special Marine Warning	LIX		55 min
Apr 15, 4:06 AM CDT	Small Craft Advisory	LIX		12 hr
Apr 15, 4:36 AM CDT	Severe Thunderstorm Warning	LIX	East Feliciana	24 min
Apr 15, 4:46 AM CDT	Special Marine Warning	LIX		44 min
Apr 15, 4:58 AM CDT	Special Weather Statement	LIX	Saint Helena	47 min
Apr 15, 5:03 AM CDT	Special Weather Statement	LIX	Pointe Coupee	42 min
Apr 15, 5:59 AM CDT	Special Weather Statement	LIX	Ascension, Livingston, Saint James	31 min
Apr 15, 6:11 AM CDT	Special Weather Statement	LIX	Washington	34 min
Apr 15, 6:16 AM CDT	Special Marine Warning	LIX		59 min
Apr 15, 6:22 AM CDT	Special Weather Statement	LIX	Assumption	53 min
Apr 15, 6:38 AM CDT	River Flood Warning	LIX	Washington	3 days
Apr 15, 7:01 AM CDT	Special Weather Statement	LIX	Orleans, Saint Charles	44 min
Apr 15, 7:10 AM CDT	Special Marine Warning	LIX		65 min
Apr 15, 7:40 AM CDT	Special Weather Statement	LIX	Terrebonne	50 min
Apr 15, 7:45 AM CDT	Special Weather Statement	LIX	Orleans	30 min
Apr 15, 7:57 AM CDT	Special Marine Warning	LIX		63 min
Apr 15, 8:01 AM CDT	Special Marine Warning	LIX		29 min
Apr 15, 8:04 AM CDT	Special Marine Warning	LIX		56 min
Apr 15, 8:16 AM CDT	Special Weather Statement	LIX	Jefferson, Plaquemines	89 min
Apr 15, 8:40 AM CDT	Special Marine Warning	LIX		95 min
Apr 15, 8:57 AM CDT	Special Marine Warning	LIX		63 min
Apr 15, 9:58 AM CDT	Special Marine Warning	LIX		92 min
Apr 15, 10:04 AM CDT	River Flood Warning	LIX	Ascension, Livingston	21 days
Apr 15, 10:04 AM CDT	River Flood Warning	LIX	Ascension, Livingston	5 days
Apr 15, 10:14 AM CDT	River Flood Warning	LIX	Tangipahoa	27 hr
Apr 15, 11:15 AM CDT	Special Weather Statement	LIX	Lafourche	60 min
Apr 15, 11:16 AM CDT	River Flood Warning	LIX	Tangipahoa	21 hr
Apr 15, 11:21 AM CDT	Special Marine Warning	LIX		54 min
Apr 15, 11:49 AM CDT	Special Marine Warning	LIX		42 min
Apr 15, 12:39 PM CDT	Special Marine Warning	LIX		66 min
Apr 15, 12:46 PM CDT	Special Marine Warning	LIX		59 min
Apr 15, 1:38 PM CDT	Special Marine Warning	LIX		67 min
Apr 15, 1:41 PM CDT	Special Marine Warning	LIX		12 min
Apr 15, 2:40 PM CDT	Special Marine Warning	LIX		45 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.