Alert archive / Louisiana / Mesoscale Discussions in 2003

Mesoscale Discussion 419

April 6, 200317 parishes in Louisiana; 5 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 6, 2003, 3:26 PM CDT for 17 parishes in Louisiana; 5 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 6, 2003, 3:26 PM CDT (20:26 UTC)
Expired: Apr 6, 2003, 5:30 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 22 counties

Bienville Parish, LA, Caldwell Parish, LA, De Soto Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Union Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Angelina County, TX, Nacogdoches County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX

The watches that followed

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

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 8.4 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-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: 1292 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 492 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 259 m²/s²
0-3 km storm-relative helicity: 405 m²/s²
Significant tornado parameter: 2.5
Supercell composite: 20.3

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 6, 7:38 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 16 more	97 min
Apr 6, 7:50 AM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Caddo, Claiborne, East Carroll, Franklin and 9 more	5 hr
Apr 6, 10:00 AM CDT	Mesoscale Discussion	SPC	East Carroll, Madison, West Carroll	2 hr
Apr 6, 10:20 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 16 more	55 min
Apr 6, 10:30 AM CDT	Tornado Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 20 more	6 hr
Apr 6, 12:03 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 14 more	117 min
Apr 6, 3:45 PM CDT	Tornado Watch	SPC	Allen, Avoyelles, Beauregard, Bienville, Bossier, Caddo and 26 more	5 hr
Apr 6, 5:35 PM CDT	Mesoscale Discussion	SPC	Allen, Avoyelles, Beauregard, Bienville, Bossier, Caddo and 26 more	115 min
Apr 6, 6:23 PM CDT	Mesoscale Discussion	SPC	Avoyelles, Beauregard, Bienville, Bossier, Caldwell, Catahoula and 23 more	97 min
Apr 6, 6:50 PM CDT	Tornado Watch	SPC	Avoyelles, Caldwell, Catahoula, Concordia, East Carroll, Evangeline and 11 more	6 hr
Apr 5, 6:11 PM CST	Mesoscale Discussion	SPC	Baylor, Briscoe, Cottle, Crosby, Dickens, Floyd and 9 more	64 min
Apr 5, 6:35 PM CST	Mesoscale Discussion	SPC	Archer, Clay, Collin, Cooke, Dallas, Delta and 23 more	115 min
Apr 5, 6:40 PM CST	Tornado Watch	SPC	Briscoe, Childress, Cottle, Crosby, Dickens, Fisher and 16 more	5 hr
Apr 5, 8:04 PM CST	Mesoscale Discussion	SPC	Archer, Baylor, Clay, Collin, Cooke, Dallas and 25 more	116 min
Apr 5, 9:20 PM CST	Mesoscale Discussion	SPC	Archer, Camp, Clay, Collin, Cooke, Dallas and 31 more	55 min
Apr 5, 9:35 PM CST	Tornado Watch	SPC	Archer, Bowie, Camp, Cass, Clay, Collin and 38 more	5 hr
Apr 5, 10:26 PM CST	Mesoscale Discussion	SPC	Baylor, Childress, Cottle, Dickens, Fisher, Foard and 11 more	64 min
Apr 5, 11:43 PM CST	Mesoscale Discussion	SPC	Archer, Camp, Clay, Collin, Cooke, Dallas and 31 more	92 min
Apr 6, 3:13 AM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Camp, Cass, Cherokee, Clay and 39 more	107 min
Apr 6, 3:39 AM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Camp, Cass, Cherokee, Clay and 39 more	66 min
Apr 6, 4:50 AM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Brown, Callahan, Coke, Coleman and 27 more	115 min
Apr 6, 5:35 AM CDT	Severe Thunderstorm Watch	SPC	Wichita	4 hr
Apr 6, 9:12 AM CDT	Mesoscale Discussion	SPC	Anderson, Bosque, Camp, Cass, Cherokee, Collin and 41 more	2 hr
Apr 6, 12:40 PM CDT	Tornado Watch	SPC	Anderson, Brazos, Burleson, Cherokee, Collin, Cooke and 33 more	5 hr
Apr 6, 2:55 PM CDT	Severe Thunderstorm Watch	SPC	Bowie, Delta, Lamar, Red River	5 hr
Apr 6, 3:00 PM CDT	Mesoscale Discussion	SPC	Anderson, Brazos, Cherokee, Delta, Freestone, Grimes and 21 more	90 min

Nearby

Mesoscale Discussions in Louisiana, 2003 Mesoscale Discussions in Texas, 2003 Every mesoscale discussion in 2003

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.