Alert archive / Mississippi / Mesoscale Discussions in 2004

Mesoscale Discussion 92

February 5, 200412 counties in Alabama; 21 parishes in Louisiana; 28 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Feb 5, 2004, 4:43 PM CST for 12 counties in Alabama; 21 parishes in Louisiana; 28 counties in Mississippi. It was in force for 32 min.

The area

The outline as issued.

The facts

Issued
Feb 5, 2004, 4:43 PM CST (22:43 UTC)
Expired
Feb 5, 2004, 5:15 PM CST
In force
32 min
Issued by
the Storm Prediction Center
All 61 counties

Autauga County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Dallas County, AL, Greene County, AL, Hale County, AL, Marengo County, AL, Perry County, AL, Sumter County, AL, Washington County, AL, Wilcox County, AL, Ascension Parish, LA, Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Jefferson Parish, LA, Lafourche Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, St. Mary Parish, LA, Tangipahoa Parish, LA, Terrebonne Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, Amite County, MS, Clarke County, MS, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Neshoba County, MS, Newton County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 10.7 hours before the alert went out and 71 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 12:00Z on 2004-02-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 772 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 12:00Z on 2004-02-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 338 square meters per square second.19395878Sfc1 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
772 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
446 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
338 m²/s²
0-3 km storm-relative helicity
542 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.2

Open this sounding in Storm Lab

The text

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

538 
ACUS11 KWNS 052243
SWOMCD
SPC MCD 052243 
ALZ000-MSZ000-LAZ000-052315-

MESOSCALE DISCUSSION 0092
NWS STORM PREDICTION CENTER NORMAN OK
0443 PM CST THU FEB 05 2004

AREAS AFFECTED...LOWER MS VLY

CONCERNING...TORNADO WATCH 6...

VALID 052243Z - 052315Z

SURFACE FRONT HAS BECOME STATIONARY ACROSS CNTRL AL SWWD INTO SRN MS
AND SCNTRL LA. BAND OF TSTMS CONTINUES ALONG/NORTH OF THE FRONT. 
SEVERAL CELLS WITHIN THE BAND HAVE TAKEN ON SMALL SCALE BOWS/LEWPS
GIVEN THE UNIDIRECTIONAL SSWLY FLOW THROUGH THE COLUMN.  THESE TSTMS
MAY POSE A DAMAGING WIND OR BRIEF TORNADO THREATS.  THERE ARE A
COUPLE OF NEGATIVES FOR WIDESPREAD SEVERE WEATHER.  WATER VAPOR
IMAGERY SHOWS SOME INCREASE IN UPPER LEVEL RIDGING NOTED BY
ANTICYCLONIC ARCING MID/HIGH  LEVEL CLOUDS OVER THE WRN GULF BASIN
AHEAD OF NEXT IMPULSE READY TO EJECT NEWD FROM S TX. 
MOREOVER...MIDLEVEL TEMPERATURES ARE SOMEWHAT HIGH TO SUPPORT
VIGOROUS UPDRAFTS.  NONETHELESS...LOW LEVEL FLOW IS QUITE STRONG AND
IS RICH WITH LOW LEVEL HELICITY.  THIS MAY COMPENSATE FOR THE MODEST
BUOYANCY AND SOMEWHAT UNFAVORABLE UPPER LEVEL RIDGING. AS SUCH...A
NEW TORNADO WATCH WILL BE ISSUED FOR PARTS OF THE AREA BY 23 UTC. 
THE SEVERE THREAT MAY ACTUALLY BE HIGHER LATER THIS EVENING WHEN THE
NEXT IMPULSE APPROACHES THE LOWER MS VLY.

..RACY.. 02/05/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...BMX...MOB...JAN...LIX...LCH...

29299271 32918923 32918622 29259007

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 5, 9:52 AM CSTMesoscale DiscussionSPCChoctaw, Washington113 min
Feb 5, 11:35 AM CSTTornado WatchSPCAutauga, Chilton, Choctaw, Clarke, Dallas, Greene and 6 more5 hr
Feb 5, 1:11 PM CSTMesoscale DiscussionSPCChoctaw, Clarke, Greene, Hale, Marengo, Perry and 2 more2 hr
Feb 5, 3:22 PM CSTMesoscale DiscussionSPCChoctaw, Marengo, Sumter113 min
Feb 5, 4:55 PM CSTTornado WatchSPCBibb, Chilton, Choctaw, Clarke, Dallas, Greene and 10 more6 hr
Feb 4, 11:37 PM CSTMesoscale DiscussionSPCAcadia, Allen, Avoyelles, Beauregard, Calcasieu, Evangeline and 10 more83 min
Feb 5, 1:16 AM CSTMesoscale DiscussionSPCBeauregard, Bienville, De Soto, Grant, Jackson, Lincoln and 6 more119 min
Feb 5, 5:08 AM CSTMesoscale DiscussionSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Calcasieu and 27 more3 hr
Feb 5, 5:40 AM CSTTornado WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 33 more6 hr
Feb 5, 7:35 AM CSTMesoscale DiscussionSPCAcadia, Calcasieu, Cameron, East Baton Rouge, East Feliciana, Evangeline and 11 more115 min
Feb 5, 8:02 AM CSTMesoscale DiscussionSPCAcadia, Calcasieu, Cameron, East Baton Rouge, East Feliciana, Evangeline and 11 more118 min

Nearby

Mesoscale Discussions in Mississippi, 2004Mesoscale Discussions in Louisiana, 2004Mesoscale Discussions in Alabama, 2004Every mesoscale discussion 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.