Alert archive / Louisiana / Mesoscale Discussions in 2008

Mesoscale Discussion 784

May 3, 2008Mobile County, Alabama; 10 parishes in Louisiana; 8 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 3, 2008, 7:36 AM CDT for Mobile County, Alabama; 10 parishes in Louisiana; 8 counties in Mississippi. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued: May 3, 2008, 7:36 AM CDT (12:36 UTC)
Expired: May 3, 2008, 8:30 AM CDT
In force: 54 min
Issued by: the Storm Prediction Center

Counties Mobile County, AL, Ascension Parish, LA, Assumption Parish, LA, Iberville Parish, LA, Orleans Parish, LA, Saint Bernard Parish, LA, Saint Charles Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Perry County, MS, Stone County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 0.6 hours before the alert went out and 17 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: 2230 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 536 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 235 m²/s²
0-3 km storm-relative helicity: 253 m²/s²
Significant tornado parameter: 2.8
Supercell composite: 14.6

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 031236
SWOMCD
SPC MCD 031236 
ALZ000-MSZ000-LAZ000-031330-

MESOSCALE DISCUSSION 0784
NWS STORM PREDICTION CENTER NORMAN OK
0736 AM CDT SAT MAY 03 2008

AREAS AFFECTED...SE LA...SRN MS AND SRN AL

CONCERNING...TORNADO WATCH 258...

VALID 031236Z - 031330Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 258 CONTINUES.

THE SEVERE THREAT WILL PERSIST THIS MORNING ACROSS SE LA...SRN MS
AND SRN AL AS A LINEAR MCS MOVES SEWD. LARGE HAIL AND DAMAGING WINDS
WILL BE THE PRIMARY THREATS ALTHOUGH A TORNADO REMAINS POSSIBLE WITH
ROTATING CELLS EMBEDDED IN THE LINE.

SFC ANALYSIS SHOW A PREFRONTAL TROUGH OVER WRN TN AND MS WITH A
PRONOUNCED MOIST AXIS EXTENDING NWD ACROSS WRN AL WITH DEWPOINTS IN
THE MID 60S F. THE LINEAR MCS IS LOCATED ALONG AND JUST EAST OF A
35-45 KT LOW-LEVEL JET. THIS COMBINED WITH MODERATE INSTABILITY
LOCATED ACROSS MUCH OF WW 258 AND INCREASING LARGE-SCALE ASCENT
ASSOCIATED WITH AN THE SRN EXTENSION OF AN UPPER-LEVEL TROUGH
LOCATED ALONG THE MS RIVER IS SUPPORTING THE SQUALL-LINE. REGIONAL
WSR-88D VWPS SHOW ADEQUATE DEEP LAYER SHEAR AND STRONG BOUNDARY
LAYER FLOW ASSOCIATED WITH THE LOW-LEVEL JET TO CONTINUE A THREAT
FOR WIND DAMAGE. ALTHOUGH THE LOW-LEVEL SHEAR IS FORECAST TO
GRADUALLY WEAKEN LATE THIS MORNING...AN ISOLATED TORNADO THREAT MAY
PERSIST FOR A FEW MORE HOURS.

..BROYLES.. 05/03/2008

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

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

29468938 29549001 29539062 29699102 29859131 30079180
30239165 30369093 30648982 31148930 31378860 30888818
30398810 30078826 29748870 29398893

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 2, 7:09 PM CDT	Mesoscale Discussion	SPC	Colbert, Fayette, Franklin, Lamar, Lauderdale, Lawrence and 5 more	96 min
May 2, 11:04 PM CDT	Mesoscale Discussion	SPC	Colbert, Fayette, Franklin, Lamar, Lauderdale, Lawrence and 2 more	86 min
May 3, 2:16 AM CDT	Mesoscale Discussion	SPC	Colbert, Fayette, Franklin, Lamar, Lauderdale, Lawrence and 2 more	59 min
May 3, 4:07 AM CDT	Tornado Watch	SPC	Choctaw, Mobile, Washington	7 hr
May 3, 7:10 AM CDT	Severe Thunderstorm Watch	SPC	Autauga, Baldwin, Butler, Chilton, Clarke, Conecuh and 12 more	6 hr
May 3, 9:04 AM CDT	Mesoscale Discussion	SPC	Barbour, Bullock, Coffee, Dale, Geneva, Henry and 3 more	86 min
May 2, 11:38 PM CDT	Tornado Watch	SPC	Caldwell, Catahoula, Concordia, East Carroll, Franklin, Grant and 11 more	6 hr
May 3, 4:04 AM CDT	Mesoscale Discussion	SPC	East Feliciana, Pointe Coupee, Saint Helena, Saint Landry, West Feliciana	56 min
May 2, 7:48 PM CDT	Tornado Watch	SPC	Alcorn, Benton, Bolivar, Calhoun, Coahoma, DeSoto and 15 more	4 hr

Nearby

Mesoscale Discussions in Louisiana, 2008 Mesoscale Discussions in Mississippi, 2008 Mesoscale Discussions in Alabama, 2008 Every mesoscale discussion in 2008

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.