Alert archive / Louisiana / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 6, NWS New Orleans, LA

February 14, 2009Tangipahoa Parish, Washington Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Feb 14, 2009, 4:31 AM CST for Tangipahoa Parish, Washington 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: Feb 14, 2009, 4:31 AM CST (10:31 UTC)
Expired: Feb 14, 2009, 5:00 AM CST
In force: 29 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon

Counties Tangipahoa Parish, LA, Washington Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 10.5 hours before the alert went out and 74 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: 101 J/kg
Mixed-layer CIN: -41 J/kg
Mixed-layer LCL: 846 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 138 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

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 Feb 14, 3:39 AM CST, 52 minutes earlier.

Area forecast discussion, Feb 14, 3:39 AM CST, 52 minutes before

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Hazardous weather outlook, Feb 13, 6:51 PM CST, 9 hours 40 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
651 PM CST FRI FEB 13 2009

GMZ530-550-555-570-575-LAZ034>040-046>050-056>070-MSZ068>071-077-
080>082-141200-
LAKE PONTCHARTRAIN AND LAKE MAUREPAS-
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER
TO LOWER ATCHAFALAYA RIVER LA OUT 20 NM-
COASTAL WATERS FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER OUT 20 NM-
COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER
TO LOWER ATCHAFALAYA RIVER LA FROM 20 TO 60 NM-
COASTAL WATERS FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER FROM 20 TO 60 NM-POINTE COUPEE-WEST FELICIANA-
EAST FELICIANA-ST. HELENA-TANGIPAHOA-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-WILKINSON-AMITE-PIKE-WALTHALL-PEARL RIVER-
HANCOCK-HARRISON-JACKSON-
651 PM CST FRI FEB 13 2009

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

.DAY ONE...TONIGHT

WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS CAN BE EXPECTED
OVERNIGHT. WHILE SOME OF THE THUNDERSTORMS WILL PRODUCE OCCASIONAL
LIGHTNING AND HEAVY DOWNPOURS OF RAIN... ORGANIZED SEVERE
THUNDERSTORM DEVELOPMENT IS NOT ANTICIPATED.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

LATEST MODEL TRENDS SUGGEST ISOLATED STRONG THUNDERSTORMS MAY BE
POSSIBLE SATURDAY IN ADVANCE OF A SLOW MOVING COLD FRONT. THE MAIN
THREATS WILL LIKELY BE WIND GUSTS UP TO 50 MPH...FREQUENT LIGHTNING
AND LOCALLY HEAVY RAINFALL. THIS FRONT IS EXPECTED TO BECOME
STATIONARY NEAR THE COAST BY SATURDAY NIGHT.

ISOLATED NON SEVERE THUNDERSTORMS ARE POSSIBLE SATURDAY NIGHT AND
EARLY SUNDAY ALONG A WARM FRONT. THUNDERSTORMS ARE ALSO POSSIBLE
AGAIN TUESDAY AND TUESDAY NIGHT BETWEEN A NORTH MOVING WARM FRONT
TUESDAY AND AN EAST MOVING COLD FRONT EARLY WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

In the hours before

Special weather statement, Feb 14, 12:30 AM CST, 4 hours 1 minute before

MSZ068-140730-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1230 AM CST SAT FEB 14 2009

...STRONG THUNDERSTORM MOVING EAST AFFECTING WILKINSON COUNTY...

AT 1224 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 7 MILES NORTH OF SIMMESPORT...OR ABOUT 15 MILES
WEST OF FORT ADAMS...MOVING EAST AT 40 MPH.

THE STRONG THUNDERSTORM WILL BE NEAR...
  FORT ADAMS BY 1245 AM...
  WOODVILLE BY 110 AM...

THE PRIMARY THREAT FROM THIS STORM IS PEA TO MARBLE SIZE HAIL. SEEK
SHELTER IN A SAFE HOME OR BUILDING UNTIL THIS STORM HAS PASSED.

Special weather statement, Feb 14, 2:24 AM CST, 2 hours 7 minutes before

LAZ034-140930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
224 AM CST SAT FEB 14 2009

...SEVERE THUNDERSTORM APPROACHING POINTE COUPEE PARISH...

AT 222 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM NEAR PALMETTO...OR ABOUT 20 MILES WEST OF
BATCHELOR...MOVING EAST AT 45 MPH. IF THIS THUNDERSTORM MAINTAINS
THE CURRENT STRENGTH...A SEVERE THUNDERSTORM OR TORNADO WARNING MAY
BE NECESSARY BEFORE 245 AM.

THE STRONG TO SEVERE THUNDERSTORM WILL BE NEAR...
  6 MILES SOUTH OF BATCHELOR BY 250 AM...
  MORGANZA BY 255 AM...

Local storm report, Feb 14, 3:08 AM CST, 1 hour 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
308 AM CST SAT FEB 14 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0303 AM     TSTM WND DMG     BATCHELOR               30.84N 91.66W
02/14/2009                   POINTE COUPEE      LA   LAW ENFORCEMENT

            ROOF OFF AN OLD HOUSE NEAR BAYOU LATENACHE IN BATCHELOR
            AREA. LARGE HAIL ALSO REPORTED BUT NO SIZE ON HAIL.

&&

RSW

Local storm report, Feb 14, 4:29 AM CST, 2 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 13, 6:47 PM CST	Special Marine Warning	LIX		59 min
Feb 14, 2:36 AM CST	Severe Thunderstorm Warning	LIX	Pointe Coupee, West Feliciana	39 min
Feb 14, 3:14 AM CST	Severe Thunderstorm Warning	LIX	East Feliciana, Pointe Coupee, West Feliciana	46 min
Feb 14, 3:56 AM CST	Severe Thunderstorm Warning	LIX	East Feliciana, Saint Helena, Tangipahoa	34 min
Feb 14, 4:15 AM CST	Areal Flood Advisory	LIX	Jefferson, Orleans	131 days
Feb 14, 8:17 AM CST	Special Marine Warning	LIX		88 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2009 Every severe thunderstorm warning in 2009

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.