Alert archive / Louisiana / Mesoscale Discussions in 2005

Mesoscale Discussion 502

April 6, 20054 counties in Arkansas; 17 parishes in Louisiana; 17 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 6, 2005, 10:40 AM CDT for 4 counties in Arkansas; 17 parishes in Louisiana; 17 counties in Mississippi. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued: Apr 6, 2005, 10:40 AM CDT (15:40 UTC)
Expired: Apr 6, 2005, 11:45 AM CDT
In force: 65 min
Issued by: the Storm Prediction Center

All 38 counties

Ashley County, AR, Chicot County, AR, Desha County, AR, Drew County, AR, Caldwell Parish, LA, Catahoula Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Richland Parish, LA, Tensas Parish, LA, Union Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Attala County, MS, Bolivar County, MS, Carroll County, MS, Claiborne County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Leake County, MS, Leflore County, MS, Madison County, MS, Montgomery County, MS, Sharkey County, MS, Sunflower County, MS, Warren County, MS, Washington County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 153 km from the middle of the area, began a volume at 15:41 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 131Apr 6, 11:05 AM CDT

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 3.7 hours before the alert went out and 144 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: 268 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 618 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 278 m²/s²
0-3 km storm-relative helicity: 332 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.7

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 5, 8:25 PM CDT	Severe Thunderstorm Watch	SPC	Columbia, Hempstead, Lafayette, Little River, Miller, Nevada and 1 more	8 hr
Apr 5, 8:30 PM CDT	Severe Thunderstorm Watch	SPC	Baxter, Benton, Boone, Carroll, Clark, Conway and 27 more	5 hr
Apr 5, 10:40 PM CDT	Mesoscale Discussion	SPC	Ashley, Bradley, Union	2 hr
Apr 5, 11:41 PM CDT	Mesoscale Discussion	SPC	Arkansas, Baxter, Calhoun, Cleburne, Cleveland, Conway and 31 more	34 min
Apr 6, 7:46 AM CDT	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 30 more	119 min
Apr 6, 12:46 PM CDT	Mesoscale Discussion	SPC	Baxter, Benton, Boone, Carroll, Cleburne, Conway and 17 more	119 min
Apr 6, 1:55 PM CDT	Tornado Watch	SPC	Baxter, Clay, Cleburne, Craighead, Crittenden, Cross and 19 more	7 hr
Apr 6, 3:18 PM CDT	Mesoscale Discussion	SPC	Baxter, Clay, Cleburne, Craighead, Crittenden, Cross and 19 more	87 min
Apr 6, 5:44 PM CDT	Mesoscale Discussion	SPC	Arkansas, Baxter, Clay, Cleburne, Craighead, Crittenden and 20 more	91 min
Apr 6, 2:55 AM CDT	Tornado Watch	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Calcasieu and 36 more	7 hr
Apr 6, 5:45 AM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Calcasieu and 36 more	90 min
Apr 6, 7:00 AM CDT	Tornado Watch	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Cameron and 27 more	6 hr
Apr 6, 9:29 AM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Cameron and 27 more	2 hr
Apr 6, 11:05 AM CDT	Tornado Watch	SPC	Ascension, Assumption, Concordia, East Baton Rouge, East Carroll, East Feliciana and 22 more	8 hr
Apr 6, 1:21 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, Concordia, East Baton Rouge, East Carroll, East Feliciana and 22 more	84 min
Apr 6, 3:43 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, Concordia, East Baton Rouge, East Carroll, East Feliciana and 22 more	92 min
Apr 6, 6:01 PM CDT	Mesoscale Discussion	SPC	Orleans, Saint Bernard, Saint Tammany, Washington	59 min
Apr 6, 6:45 PM CDT	Tornado Watch	SPC	Washington	6 hr
Apr 6, 11:05 AM CDT	Tornado Watch	SPC	George, Greene, Harrison, Jackson, Wayne	8 hr
Apr 6, 4:53 PM CDT	Mesoscale Discussion	SPC	Alcorn, Tishomingo	37 min

Nearby

Mesoscale Discussions in Louisiana, 2005 Mesoscale Discussions in Mississippi, 2005 Mesoscale Discussions in Arkansas, 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; radar from the NEXRAD Level II archive.