Alert archive / Louisiana / Mesoscale Discussions in 2012
Mesoscale Discussion 453
The Storm Prediction Center issued this mesoscale discussion at Apr 5, 2012, 3:30 AM CDT for Ashley County, Chicot County, Union County, Arkansas; 49 parishes in Louisiana; 45 counties in Mississippi. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 5, 2012, 3:30 AM CDT (08:30 UTC)
- Expired
- Apr 5, 2012, 5:30 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
All 97 counties
Ashley County, AR, Chicot County, AR, Union County, AR, Acadia Parish, LA, Ascension Parish, LA, Assumption Parish, LA, Avoyelles Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Jackson Parish, LA, Jefferson Parish, LA, Lafayette Parish, LA, Lafourche Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Livingston Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Orleans Parish, LA, Ouachita Parish, LA, Plaquemines Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Richland 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, St. Mary Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, Terrebonne Parish, LA, Union Parish, LA, Vermilion Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Attala County, MS, Carroll County, MS, Claiborne County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jackson County, MS, Jasper County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Leake County, MS, Leflore County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Newton County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Warren County, MS, Washington County, MS, Wayne 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
Slidell Radar S, LA (KSIL), launched 00:00Z, 8.5 hours before the alert went out and 52 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.
- Mixed-layer CAPE
- 593 J/kg
- Mixed-layer CIN
- -175 J/kg
- Mixed-layer LCL
- 1126 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 58 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 4, 8:31 PM CDT | Mesoscale Discussion | SPC | Calhoun, Clark, Columbia, Conway, Crawford, Dallas and 24 more | 119 min |
| Apr 5, 1:35 AM CDT | Mesoscale Discussion | SPC | Ashley, Chicot | 85 min |
| Apr 5, 1:53 AM CDT | Tornado Watch | SPC | Ashley, Chicot | 9 hr |
| Apr 5, 7:36 AM CDT | Mesoscale Discussion | SPC | Chicot | 54 min |
| Apr 5, 12:09 PM CDT | Mesoscale Discussion | SPC | Clay, Craighead, Crittenden, Greene, Mississippi, Randolph | 96 min |
| Apr 5, 12:18 PM CDT | Severe Thunderstorm Watch | SPC | Crittenden, Mississippi | 5 hr |
| Apr 4, 8:25 PM CDT | Mesoscale Discussion | SPC | Acadia, Allen, Ascension, Assumption, Beauregard, Calcasieu and 21 more | 95 min |
| Apr 5, 3:56 AM CDT | Tornado Watch | SPC | Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 16 more | 6 hr |
| Apr 5, 9:14 AM CDT | Severe Thunderstorm Watch | SPC | Greene, Perry, Wayne | 8 hr |
| Apr 5, 10:41 AM CDT | Mesoscale Discussion | SPC | Greene, Wayne | 94 min |
| Apr 5, 10:43 AM CDT | Severe Thunderstorm Watch | SPC | Clarke, Covington, Forrest, Franklin, Jasper, Jefferson Davis and 7 more | 4 hr |
| Apr 5, 2:22 PM CDT | Mesoscale Discussion | SPC | Alcorn, Benton, Calhoun, Chickasaw, DeSoto, Itawamba and 14 more | 53 min |
Nearby
Mesoscale Discussions in Louisiana, 2012Mesoscale Discussions in Mississippi, 2012Mesoscale Discussions in Arkansas, 2012Every mesoscale discussion in 2012
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.