Alert archive / Louisiana / Tornado Watches in 2004

Tornado Watch 898

November 24, 2004Plaquemines Parish, Saint Bernard Parish, Louisiana; Harrison County, Jackson County, Mississippi

The Storm Prediction Center issued this tornado watch at Nov 24, 2004, 5:55 AM CST for Plaquemines Parish, Saint Bernard Parish, Louisiana; Harrison County, Jackson County, Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Nov 24, 2004, 5:55 AM CST (11:55 UTC)
Expired
Nov 24, 2004, 8:00 AM CST
In force
2 hr
Issued by
the Storm Prediction Center

Counties Plaquemines Parish, LA, Saint Bernard Parish, LA, Harrison County, MS, Jackson County, MS

The radar

The Mobile radar (KMOB), 149 km from the middle of the area, began a volume at 11:59 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Warnings issued inside it

4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Nov 24, 5:55 AM CSTSevere Thunderstorm WarningLIXHarrison, Jackson50 min
Nov 24, 6:03 AM CSTSevere Thunderstorm WarningLIXPlaquemines57 min
Nov 24, 6:41 AM CSTSevere Thunderstorm WarningLIXJackson49 min
Nov 24, 7:01 AM CSTSevere Thunderstorm WarningLIXPlaquemines29 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 11.9 hours before the alert went out and 91 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 00:00Z on 2004-11-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 866 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 00:00Z on 2004-11-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 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
866 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
805 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
118 m²/s²
Significant tornado parameter
0.5
Supercell composite
2.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

229 
WWUS20 KWNS 241156
SEL8  
SPC WW 241155
LAZ000-MSZ000-CWZ000-241400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 898
NWS STORM PREDICTION CENTER NORMAN OK
555 AM CST WED NOV 24 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       EXTREME SOUTHEAST LOUISIANA
       EXTREME SOUTHERN MISSISSIPPI
       COASTAL WATERS

EFFECTIVE THIS WEDNESDAY MORNING FROM 555 AM UNTIL 800 AM CST.

TORNADOES...HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS ALONG AND 40 STATUTE MILES EAST AND WEST
OF A LINE FROM 40 MILES EAST NORTHEAST OF GULFPORT MISSISSIPPI TO
25 MILES SOUTH OF BOOTHVILLE LOUISIANA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 895. WATCH NUMBER 895 WILL NOT BE IN EFFECT AFTER 555
AM CST. CONTINUE...WW 896...WW 897...

DISCUSSION...LINE OF STRONG/SEVERE THUNDERSTORMS OVER SOUTHEAST LA
WILL MOVE OFFSHORE DURING THE NEXT 2 HOURS.  IN THE
MEANTIME...STRONG WINDS FIELDS AND AMPLE MOISTURE/INSTABILITY WILL
MAINTAIN A RISK OF SEVERE THUNDERSTORMS AND POSSIBLE TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 25035.


...HART

303,0874 285,0884 285,0900 303,0890

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 23, 7:50 PM CSTTornado WatchSPCSabine6 hr
Nov 23, 7:53 PM CSTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 20 more37 min
Nov 23, 8:15 PM CSTTornado WatchSPCAllen, Avoyelles, Beauregard, Caldwell, Catahoula, Concordia and 21 more6 hr
Nov 23, 9:14 PM CSTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Catahoula, Concordia, East Carroll and 7 more2 hr
Nov 23, 10:01 PM CSTMesoscale DiscussionSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 38 more119 min
Nov 23, 11:00 PM CSTSevere Thunderstorm WatchSPCAcadia, Ascension, Assumption, Calcasieu, Cameron, Iberia and 15 more7 hr
Nov 24, 12:30 AM CSTMesoscale DiscussionSPCSaint Tammany, Tangipahoa, Washington30 min
Nov 24, 12:45 AM CSTTornado WatchSPCSaint Helena, Tangipahoa, Washington5 hr
Nov 24, 1:28 AM CSTMesoscale DiscussionSPCAvoyelles, Concordia, East Baton Rouge, East Carroll, East Feliciana, Evangeline and 9 more32 min
Nov 24, 1:45 AM CSTTornado WatchSPCEast Baton Rouge, East Feliciana, Livingston, Pointe Coupee, Saint Helena, Saint Landry and 2 more4 hr
Nov 24, 2:43 AM CSTMesoscale DiscussionSPCTangipahoa, Washington62 min
Nov 24, 2:50 AM CSTTornado WatchSPCAscension, Assumption, East Baton Rouge, Iberville, Jefferson, Lafourche and 11 more3 hr
Nov 24, 5:35 AM CSTMesoscale DiscussionSPCJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard25 min
Nov 23, 6:35 PM CSTTornado WatchSPCAlcorn, Attala, Benton, Calhoun, Carroll, Chickasaw and 28 more7 hr
Nov 23, 9:00 PM CSTMesoscale DiscussionSPCAlcorn, Itawamba, Prentiss, Tishomingo2 hr
Nov 23, 9:20 PM CSTTornado WatchSPCItawamba, Lowndes, Monroe, Tishomingo7 hr
Nov 24, 3:35 AM CSTMesoscale DiscussionSPCLowndes25 min
Nov 24, 4:57 AM CSTMesoscale DiscussionSPCClarke, Forrest, George, Greene, Lamar, Pearl River and 3 more63 min
Nov 24, 5:20 AM CSTTornado WatchSPCGeorge, Jackson6 hr
Nov 24, 10:16 AM CSTMesoscale DiscussionSPCAlcorn, Benton, Lafayette, Marshall, Prentiss, Tippah and 1 more2 hr

Nearby

Tornado Watches in Louisiana, 2004Tornado Watches in Mississippi, 2004Every tornado watch in 2004

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; radar from the NEXRAD Level II archive.