Alert archive / Louisiana / Mesoscale Discussions in 2005

Mesoscale Discussion 462

March 31, 200522 parishes in Louisiana; 10 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Mar 31, 2005, 3:27 PM CST for 22 parishes in Louisiana; 10 counties in Mississippi. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Mar 31, 2005, 3:27 PM CST (21:27 UTC)
Expired: Mar 31, 2005, 5:00 PM CST
In force: 93 min
Issued by: the Storm Prediction Center

All 32 counties

Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Lafayette Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Pointe Coupee 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 Landry Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Amite County, MS, George County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Pike County, MS, Stone County, MS, Walthall County, MS, Wilkinson County, MS

The watches that followed

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

Severe Thunderstorm Watch 116Mar 31, 5:50 PM CST

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 9.5 hours before the alert went out and 31 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: 2364 J/kg
Mixed-layer CIN: -15 J/kg
Mixed-layer LCL: 518 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 123 m²/s²
0-3 km storm-relative helicity: 186 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 6.8

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
Mar 31, 11:40 AM CST	Mesoscale Discussion	SPC	Acadia, Ascension, Assumption, Avoyelles, East Baton Rouge, East Feliciana and 18 more	2 hr
Mar 31, 12:15 PM CST	Severe Thunderstorm Watch	SPC	Ascension, Assumption, Avoyelles, East Baton Rouge, East Feliciana, Iberville and 19 more	6 hr
Mar 31, 2:15 PM CST	Mesoscale Discussion	SPC	Bossier, Caddo, De Soto	2 hr
Mar 31, 5:28 PM CST	Mesoscale Discussion	SPC	Ascension, East Baton Rouge, East Feliciana, Iberville, Livingston, Orleans and 11 more	62 min
Mar 31, 5:50 PM CST	Severe Thunderstorm Watch	SPC	Catahoula, Concordia, East Baton Rouge, East Feliciana, Iberville, Livingston and 7 more	6 hr
Mar 30, 7:56 PM CST	Mesoscale Discussion	SPC	Alcorn, Benton, Calhoun, Chickasaw, DeSoto, Itawamba and 14 more	94 min
Mar 30, 9:50 PM CST	Severe Thunderstorm Watch	SPC	Itawamba, Monroe	6 hr
Mar 30, 10:11 PM CST	Mesoscale Discussion	SPC	Attala, Carroll, Choctaw, Claiborne, Clarke, Copiah and 37 more	94 min
Mar 31, 12:53 AM CST	Mesoscale Discussion	SPC	Amite, Clarke, Covington, Forrest, Greene, Jasper and 19 more	97 min
Mar 31, 1:15 AM CST	Severe Thunderstorm Watch	SPC	Chickasaw, Choctaw, Clarke, Clay, Forrest, Greene and 14 more	7 hr
Mar 31, 5:34 AM CST	Mesoscale Discussion	SPC	Clarke, Forrest, Greene, Jasper, Jones, Kemper and 6 more	116 min
Mar 31, 6:53 AM CST	Mesoscale Discussion	SPC	Clarke, George, Greene, Perry, Wayne	67 min

Nearby

Mesoscale Discussions in Louisiana, 2005 Mesoscale Discussions in Mississippi, 2005 Every mesoscale discussion in 2005

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.