Alert archive / Louisiana / Mesoscale Discussions in 2003

Mesoscale Discussion 117

February 21, 20034 states

The Storm Prediction Center issued this mesoscale discussion at Feb 21, 2003, 10:22 PM CST for 4 states. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued: Feb 21, 2003, 10:22 PM CST (04:22 UTC)
Expired: Feb 22, 2003, 12:15 AM CST
In force: 113 min
Issued by: the Storm Prediction Center

All 59 counties

Baldwin County, AL, Butler County, AL, Clarke County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Escambia County, AL, Mobile County, AL, Monroe County, AL, Washington County, AL, Escambia County, FL, Okaloosa County, FL, Santa Rosa County, FL, 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 Bernard 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, West Feliciana Parish, LA, Amite County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS, Wilkinson County, MS

The radar

The Mobile radar (KMOB), 77 km from the middle of the area, began a volume at 04:22 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 watches that followed

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

Tornado Watch 16Feb 22, 12:35 AM CST

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 4.4 hours before the alert went out and 81 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: 199 J/kg
Mixed-layer CIN: -82 J/kg
Mixed-layer LCL: 458 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 440 m²/s²
0-3 km storm-relative helicity: 510 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 5.9

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
Feb 21, 7:26 PM CST	Mesoscale Discussion	SPC	Baldwin, Clarke, Mobile, Washington	2 hr
Feb 21, 8:15 PM CST	Tornado Watch	SPC	Baldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 4 more	6 hr
Feb 21, 9:03 PM CST	Mesoscale Discussion	SPC	Autauga, Bibb, Blount, Chilton, Choctaw, Coosa and 22 more	3 hr
Feb 21, 9:30 PM CST	Severe Thunderstorm Watch	SPC	Autauga, Bibb, Calhoun, Chilton, Choctaw, Clay and 20 more	7 hr
Feb 21, 10:40 PM CST	Mesoscale Discussion	SPC	Autauga, Bibb, Calhoun, Chilton, Choctaw, Clay and 20 more	2 hr
Feb 21, 11:14 PM CST	Mesoscale Discussion	SPC	Blount, Calhoun, Cherokee, Cleburne, Cullman, DeKalb and 16 more	4 hr
Feb 21, 11:40 PM CST	Tornado Watch	SPC	Barbour, Bullock, Coffee, Dale, Geneva, Henry and 5 more	6 hr
Feb 22, 12:35 AM CST	Tornado Watch	SPC	Autauga, Baldwin, Bibb, Bullock, Butler, Calhoun and 37 more	5 hr
Feb 22, 2:47 AM CST	Mesoscale Discussion	SPC	Calhoun, Cherokee, Cleburne, DeKalb, Etowah, Jackson and 4 more	3 hr
Feb 22, 3:35 AM CST	Tornado Watch	SPC	Blount, Calhoun, Chambers, Cherokee, Chilton, Clay and 12 more	2 hr
Feb 22, 3:51 AM CST	Mesoscale Discussion	SPC	Autauga, Baldwin, Barbour, Bibb, Bullock, Butler and 43 more	114 min
Feb 22, 5:19 AM CST	Mesoscale Discussion	SPC	Barbour, Henry, Houston, Russell	56 min
Feb 22, 5:50 AM CST	Tornado Watch	SPC	Henry, Houston	5 hr
Feb 22, 9:14 AM CST	Mesoscale Discussion	SPC	DeKalb, Jackson, Marshall	2 hr
Feb 22, 10:35 AM CST	Tornado Watch	SPC	DeKalb, Jackson	5 hr
Feb 21, 6:18 PM CST	Mesoscale Discussion	SPC	Baker, Bradford, Clay, Columbia, Duval, Hamilton and 7 more	3 hr
Feb 22, 9:59 AM CST	Mesoscale Discussion	SPC	Baker, Duval, Nassau	61 min
Feb 22, 10:55 AM CST	Tornado Watch	SPC	Alachua, Baker, Bradford, Clay, Columbia, Duval and 6 more	5 hr
Feb 22, 11:55 AM CST	Mesoscale Discussion	SPC	Brevard, Charlotte, DeSoto, Glades, Hardee, Highlands and 11 more	3 hr
Feb 22, 12:33 PM CST	Mesoscale Discussion	SPC	Brevard, Charlotte, DeSoto, Dixie, Glades, Hardee and 13 more	117 min
Feb 22, 12:49 PM CST	Mesoscale Discussion	SPC	Alachua, Bradford, Clay, Duval, Nassau, Putnam and 1 more	116 min
Feb 22, 2:48 PM CST	Mesoscale Discussion	SPC	Brevard, Charlotte, DeSoto, Flagler, Hardee, Highlands and 14 more	27 min
Feb 21, 10:54 PM CST	Mesoscale Discussion	SPC	Beauregard, Bienville, Bossier, Caddo, De Soto, Natchitoches and 4 more	3 hr
Feb 22, 2:02 AM CST	Mesoscale Discussion	SPC	Caldwell, Catahoula, Concordia, East Carroll, Franklin, LaSalle and 6 more	3 hr

Nearby

Mesoscale Discussions in Louisiana, 2003 Mesoscale Discussions in Mississippi, 2003 Mesoscale Discussions in Alabama, 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; radar from the NEXRAD Level II archive.