Alert archive / Louisiana / Mesoscale Discussions in 2004

Mesoscale Discussion 540

May 1, 2004Natchitoches Parish, Sabine Parish, Winn Parish, Louisiana; Sabine County, San Augustine County, Shelby County, Texas

The Storm Prediction Center issued this mesoscale discussion at May 1, 2004, 7:24 AM CDT for Natchitoches Parish, Sabine Parish, Winn Parish, Louisiana; Sabine County, San Augustine County, Shelby County, Texas. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: May 1, 2004, 7:24 AM CDT (12:24 UTC)
Expired: May 1, 2004, 9:00 AM CDT
In force: 96 min
Issued by: the Storm Prediction Center

Counties Natchitoches Parish, LA, Sabine Parish, LA, Winn Parish, LA, Sabine County, TX, San Augustine County, TX, Shelby County, TX

The radar

The Shreveport radar (KSHV), 84 km from the middle of the area, began a volume at 12:24 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.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 0.4 hours before the alert went out and 183 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: 326 J/kg
Mixed-layer CIN: -239 J/kg
Mixed-layer LCL: 978 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 153 m²/s²
0-3 km storm-relative helicity: 263 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 9.3

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 30, 11:56 PM CDT	Mesoscale Discussion	SPC	Beauregard, Calcasieu, Cameron, Jefferson Davis	94 min
May 1, 12:50 AM CDT	Severe Thunderstorm Watch	SPC	Bossier, Caddo	6 hr
May 1, 2:38 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 10 more	37 min
May 1, 3:10 AM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Claiborne, De Soto, Jackson, Lincoln and 7 more	6 hr
May 1, 5:13 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 6 more	92 min
May 1, 9:45 AM CDT	Tornado Watch	SPC	Allen, Beauregard, Calcasieu, Cameron, Jefferson Davis, Vernon	5 hr
May 1, 1:45 PM CDT	Mesoscale Discussion	SPC	East Baton Rouge, East Feliciana, Iberville, Livingston, Saint Helena, Saint Tammany and 3 more	3 hr
May 1, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	Washington	5 hr
Apr 30, 7:00 PM CDT	Mesoscale Discussion	SPC	Bosque, Brown, Coleman, Comanche, Concho, Eastland and 11 more	90 min
Apr 30, 7:22 PM CDT	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Cass, Cherokee, Delta and 25 more	83 min
Apr 30, 7:40 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bowie, Camp, Delta, Ellis, Fannin and 20 more	5 hr
Apr 30, 8:14 PM CDT	Mesoscale Discussion	SPC	Archer, Clay, Collin, Cooke, Denton, Grayson and 8 more	91 min
Apr 30, 9:07 PM CDT	Mesoscale Discussion	SPC	Bosque, Brown, Comanche, Coryell, Erath, Hamilton and 8 more	53 min
Apr 30, 9:54 PM CDT	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Delta, Ellis, Franklin and 19 more	96 min
Apr 30, 10:34 PM CDT	Mesoscale Discussion	SPC	Brown, Coleman, Concho, Crockett, Edwards, Irion and 15 more	86 min
Apr 30, 11:35 PM CDT	Severe Thunderstorm Watch	SPC	Blanco, Concho, Crockett, Edwards, Gillespie, Irion and 13 more	5 hr
May 1, 1:34 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Blanco, Comal, Concho and 24 more	86 min
May 1, 1:49 AM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Cherokee, Falls, Freestone, Henderson and 5 more	86 min
May 1, 3:28 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Blanco, Concho, Crockett and 23 more	92 min
May 1, 3:41 AM CDT	Mesoscale Discussion	SPC	Austin, Brazoria, Brazos, Burleson, Chambers, Colorado and 18 more	64 min
May 1, 3:50 AM CDT	Tornado Watch	SPC	Angelina, Austin, Bastrop, Brazos, Burleson, Chambers and 25 more	6 hr
May 1, 5:40 AM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Bee, Bexar, Caldwell, DeWitt, Dimmit and 17 more	6 hr
May 1, 6:08 AM CDT	Mesoscale Discussion	SPC	Angelina, Austin, Brazos, Burleson, Chambers, Colorado and 24 more	97 min
May 1, 7:33 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bee, Bexar, Caldwell, DeWitt, Dimmit and 16 more	87 min
May 1, 7:47 AM CDT	Mesoscale Discussion	SPC	Austin, Bastrop, Brazos, Burleson, Chambers, Colorado and 23 more	88 min
May 1, 9:16 AM CDT	Mesoscale Discussion	SPC	Brazoria, Chambers, Fort Bend, Galveston, Hardin, Harris and 3 more	59 min
May 1, 9:36 AM CDT	Mesoscale Discussion	SPC	Nueces	114 min
May 1, 9:55 AM CDT	Severe Thunderstorm Watch	SPC	Brooks, Cameron, Hidalgo, Jim Hogg, Kenedy, Kleberg and 3 more	5 hr
May 1, 11:15 AM CDT	Mesoscale Discussion	SPC	Kenedy	2 hr
May 1, 1:14 PM CDT	Mesoscale Discussion	SPC	Willacy	2 hr

Nearby

Mesoscale Discussions in Louisiana, 2004 Mesoscale Discussions in Texas, 2004 Every 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; radar from the NEXRAD Level II archive.