Alert archive / Louisiana / Mesoscale Discussions in 2004

Mesoscale Discussion 2447

November 23, 200426 parishes in Louisiana; 19 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Nov 23, 2004, 7:53 PM CST for 26 parishes in Louisiana; 19 counties in Mississippi. It was in force for 37 min.

The area

The outline as issued.

The facts

Issued: Nov 23, 2004, 7:53 PM CST (01:53 UTC)
Expired: Nov 23, 2004, 8:30 PM CST
In force: 37 min
Issued by: the Storm Prediction Center

All 45 counties

Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Saint Helena Parish, LA, Saint Landry Parish, LA, Tensas Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Issaquena County, MS, Jefferson County, MS, Lawrence County, MS, Leake County, MS, Lincoln County, MS, Madison County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Warren County, MS, Wilkinson County, MS, Yazoo 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

Jackson, MS (KJAN), launched 00:00Z, 1.9 hours before the alert went out and 191 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: 1370 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 857 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 185 m²/s²
0-3 km storm-relative helicity: 198 m²/s²
Significant tornado parameter: 1.9
Supercell composite: 6.1

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
Nov 23, 7:50 PM CST	Tornado Watch	SPC	Sabine	6 hr
Nov 23, 8:15 PM CST	Tornado Watch	SPC	Allen, Avoyelles, Beauregard, Caldwell, Catahoula, Concordia and 21 more	6 hr
Nov 23, 9:14 PM CST	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Catahoula, Concordia, East Carroll and 7 more	2 hr
Nov 23, 10:01 PM CST	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 38 more	119 min
Nov 23, 11:00 PM CST	Severe Thunderstorm Watch	SPC	Acadia, Ascension, Assumption, Calcasieu, Cameron, Iberia and 15 more	7 hr
Nov 24, 12:30 AM CST	Mesoscale Discussion	SPC	Saint Tammany, Tangipahoa, Washington	30 min
Nov 24, 12:45 AM CST	Tornado Watch	SPC	Saint Helena, Tangipahoa, Washington	5 hr
Nov 24, 1:28 AM CST	Mesoscale Discussion	SPC	Avoyelles, Concordia, East Baton Rouge, East Carroll, East Feliciana, Evangeline and 9 more	32 min
Nov 24, 1:45 AM CST	Tornado Watch	SPC	East Baton Rouge, East Feliciana, Livingston, Pointe Coupee, Saint Helena, Saint Landry and 2 more	4 hr
Nov 24, 2:43 AM CST	Mesoscale Discussion	SPC	Tangipahoa, Washington	62 min
Nov 24, 2:50 AM CST	Tornado Watch	SPC	Ascension, Assumption, East Baton Rouge, Iberville, Jefferson, Lafourche and 11 more	3 hr
Nov 24, 5:35 AM CST	Mesoscale Discussion	SPC	Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard	25 min
Nov 24, 5:55 AM CST	Tornado Watch	SPC	Plaquemines, Saint Bernard	2 hr
Nov 23, 6:35 PM CST	Tornado Watch	SPC	Alcorn, Attala, Benton, Calhoun, Carroll, Chickasaw and 28 more	7 hr
Nov 23, 9:00 PM CST	Mesoscale Discussion	SPC	Alcorn, Itawamba, Prentiss, Tishomingo	2 hr
Nov 23, 9:20 PM CST	Tornado Watch	SPC	Itawamba, Lowndes, Monroe, Tishomingo	7 hr
Nov 24, 3:35 AM CST	Mesoscale Discussion	SPC	Lowndes	25 min
Nov 24, 4:57 AM CST	Mesoscale Discussion	SPC	Clarke, Forrest, George, Greene, Lamar, Pearl River and 3 more	63 min
Nov 24, 5:20 AM CST	Tornado Watch	SPC	George, Jackson	6 hr
Nov 24, 10:16 AM CST	Mesoscale Discussion	SPC	Alcorn, Benton, Lafayette, Marshall, Prentiss, Tippah and 1 more	2 hr

Nearby

Mesoscale Discussions in Louisiana, 2004 Mesoscale Discussions in Mississippi, 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.