Alert archive / Louisiana / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 150, NWS New Orleans, LA

December 22, 2015Lafourche Parish, Terrebonne Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Dec 22, 2015, 8:31 PM CST for Lafourche Parish, Terrebonne Parish, Louisiana. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Dec 22, 2015, 8:31 PM CST (02:31 UTC)
Expired: Dec 22, 2015, 9:00 PM CST
In force: 29 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Lafourche Parish, LA, Terrebonne Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 2.5 hours before the alert went out and 128 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: 84 J/kg
Mixed-layer CIN: -116 J/kg
Mixed-layer LCL: 765 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 211 m²/s²
0-3 km storm-relative helicity: 193 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS New Orleans, LA wrote its last area forecast discussion before this severe thunderstorm warning went out at Dec 22, 3:16 PM CST, 5 hours 15 minutes earlier.

Area forecast discussion, Dec 22, 3:16 PM CST, 5 hours 15 minutes before

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Hazardous weather outlook, Dec 22, 5:00 PM CST, 3 hours 31 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
500 PM CST TUE DEC 22 2015

GMZ530-532-534-536-538-550-552-555-557-570-572-575-577-LAZ034>037-
039-040-046>050-056>072-MSZ068>071-077-080>082-231400-
LAKE PONTCHARTRAIN AND LAKE MAUREPAS-MISSISSIPPI SOUND-
LAKE BORGNE-CHANDELEUR SOUND-BRETON SOUND-
COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER OUT
20 NM-
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER
TO PORT FOURCHON OUT 20 NM-
COASTAL WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER OUT 20 NM-
COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20 NM-
COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER FROM
20 TO 60 NM-
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER
TO PORT FOURCHON FROM 20 TO 60 NM-
COASTAL WATERS FROM STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER FROM 20 TO 60 NM-
COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO
60 NM-POINTE COUPEE-WEST FELICIANA-EAST FELICIANA-ST. HELENA-
WASHINGTON-ST. TAMMANY-IBERVILLE-WEST BATON ROUGE-
EAST BATON ROUGE-ASCENSION-LIVINGSTON-ASSUMPTION-ST. JAMES-
ST. JOHN THE BAPTIST-UPPER LAFOURCHE-ST. CHARLES-UPPER JEFFERSON-
ORLEANS-UPPER PLAQUEMINES-UPPER ST. BERNARD-UPPER TERREBONNE-
LOWER TERREBONNE-LOWER LAFOURCHE-LOWER JEFFERSON-
LOWER PLAQUEMINES-LOWER ST. BERNARD-NORTHERN TANGIPAHOA-
SOUTHERN TANGIPAHOA-WILKINSON-AMITE-PIKE-WALTHALL-PEARL RIVER-
HANCOCK-HARRISON-JACKSON-
500 PM CST TUE DEC 22 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
LOUISIANA...SOUTH MISSISSIPPI AND THE ADJACENT COASTAL WATERS.

.DAY ONE...TONIGHT

NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS ARE EXPECTED TONIGHT. A
FEW OF THE STORMS COULD BECOME STRONG OR EVEN SEVERE WITH THE MAIN
HAZARD BEING STRONG DAMAGING WINDS. THERE IS A MARGINAL RISK OF
SEVERE THUNDERSTORMS OVER THE ENTIRE AREA TONIGHT. RAINFALL AMOUNTS
OF 1 TO 2 INCHES WILL BE COMMON WITH LOCALLY HEAVIER AMOUNTS
POSSIBLE.

AREAS OF FOG ARE EXPECTED OVERNIGHT AND THE FOG MAY BECOME DENSE IN
SOME LOCATIONS...ESPECIALLY NEAR BODIES OF WATER. A DENSE FOG
ADVISORY MAY BE REQUIRED LATER TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE ENTIRE AREA
WEDNESDAY INTO WEDNESDAY NIGHT. THE SEVERE WEATHER HAZARDS ARE
EXPECTED TO BE MAINLY STRONG DAMAGING WINDS AND ISOLATED TORNADOES.

A FEW BOUTS OF HEAVY RAIN ARE FORECAST TO IMPACT THE REGION
WEDNESDAY WITH WIDESPREAD RAINFALL AMOUNTS OF 1 TO 3 INCHES
EXPECTED WITH LOCALLY HIGHER AMOUNTS POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT. THE ACTIVATION OF
STORM SPOTTERS...HAM RADIO OPERATORS...AND EMERGENCY MANAGEMENT
PERSONNEL IN SUPPORT OF SEVERE WEATHER OPERATIONS MAY BE NEEDED FOR
PORTIONS OF THE REGION WEDNESDAY AND WEDNESDAY NIGHT.

In the hours before

Special weather statement, Dec 22, 8:17 PM CST, 14 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
817 PM CST TUE DEC 22 2015

LAZ066-067-230300-
LOWER LAFOURCHE-LOWER TERREBONNE-
817 PM CST TUE DEC 22 2015

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN TERREBONNE
PARISH...

AT 816 PM CST...A STRONG THUNDERSTORM WAS NEAR COCODRIE...OR 25 MILES
SOUTH OF HOUMA...MOVING NORTHEAST AT 35 MPH.

WINDS IN EXCESS OF 40 MPH ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
COCODRIE...MONTEGUT...CHAUVIN...AND DULAC.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

LAT...LON 2921 9082 2954 9052 2934 9035 2930 9040
      2934 9045 2928 9048 2928 9057 2925 9059
      2922 9053 2921 9059 2925 9061 2920 9062
      2919 9061 2919 9062 2925 9063 2919 9064
      2918 9062 2911 9071
TIME...MOT...LOC 0216Z 225DEG 30KT 2921 9070

11

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 22, 7:05 PM CST	Special Marine Warning	LIX		40 min
Dec 22, 7:42 PM CST	Special Marine Warning	LIX		18 min
Dec 22, 8:17 PM CST	Special Weather Statement	LIX	Terrebonne	43 min
Dec 22, 9:03 PM CST	Special Weather Statement	LIX	Jefferson	42 min
Dec 22, 9:37 PM CST	Special Weather Statement	LIX	Lafourche	38 min
Dec 22, 10:55 PM CST	Special Marine Warning	LIX		65 min
Dec 22, 10:58 PM CST	Special Weather Statement	LIX	Lafourche	47 min
Dec 22, 11:57 PM CST	Special Marine Warning	LIX		93 min
Dec 23, 12:08 AM CST	Special Weather Statement	LIX	Ascension, Livingston, Saint James	52 min
Dec 23, 1:30 AM CST	Special Weather Statement	LIX	Jefferson	60 min
Dec 23, 1:35 AM CST	Special Marine Warning	LIX		55 min
Dec 23, 1:50 AM CST	Severe Thunderstorm Warning	LIX	Jefferson, Lafourche, Plaquemines	55 min
Dec 23, 2:02 AM CST	Severe Thunderstorm Warning	LIX	Pointe Coupee, West Feliciana	43 min
Dec 23, 2:24 AM CST	Tornado Warning	LIX	Jefferson, Lafourche	51 min
Dec 23, 2:27 AM CST	Special Marine Warning	LIX		63 min
Dec 23, 3:01 AM CST	Special Marine Warning	LIX		29 min
Dec 23, 3:20 AM CST	Tornado Warning	LIX	Plaquemines, Saint Bernard	25 min
Dec 23, 3:30 AM CST	Small Craft Advisory	LIX		18 hr
Dec 23, 3:38 AM CST	Special Marine Warning	LIX		97 min
Dec 23, 5:10 AM CST	Special Marine Warning	LIX		95 min
Dec 23, 2:26 AM CST	Tornado Warning	LIX	Wilkinson	19 min
Dec 23, 2:34 AM CST	Severe Thunderstorm Warning	LIX	Jackson	26 min
Dec 23, 5:27 AM CST	Special Weather Statement	LIX	Jackson	63 min
Dec 23, 5:32 AM CST	Severe Thunderstorm Warning	LIX	Jackson	58 min
Dec 23, 7:01 AM CST	Areal Flood Warning	LIX	Jackson	119 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2015 Every severe thunderstorm warning in 2015

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.