Alert archive / Louisiana / Mesoscale Discussions in 2013

Mesoscale Discussion 304

March 23, 201325 parishes in Louisiana; 9 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 23, 2013, 2:09 PM CDT for 25 parishes in Louisiana; 9 counties in Texas. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Mar 23, 2013, 2:09 PM CDT (19:09 UTC)
Expired: Mar 23, 2013, 3:45 PM CDT
In force: 96 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 34 counties

Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA, Gregg County, TX, Harrison County, TX, Marion County, TX, Nacogdoches County, TX, Panola County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX

The radar

The Shreveport radar (KSHV), 67 km from the middle of the area, began a volume at 19:09 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.

Severe Thunderstorm Watch 60Mar 23, 5:45 PM CDT

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 7.2 hours before the alert went out and 213 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: 777 J/kg
Mixed-layer CIN: -297 J/kg
Mixed-layer LCL: 550 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 78 m²/s²
0-3 km storm-relative helicity: 151 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 22, 8:16 PM CDT	Mesoscale Discussion	SPC	Bienville, Caldwell, Claiborne, East Carroll, Franklin, Jackson and 9 more	119 min
Mar 23, 8:49 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, De Soto, Webster	56 min
Mar 23, 10:32 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 13 more	58 min
Mar 23, 5:01 PM CDT	Mesoscale Discussion	SPC	Bienville, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 12 more	119 min
Mar 23, 5:45 PM CDT	Severe Thunderstorm Watch	SPC	Caldwell, Catahoula, Concordia, East Carroll, Franklin, Grant and 11 more	5 hr
Mar 23, 3:39 AM CDT	Mesoscale Discussion	SPC	Callahan, Coke, Coleman, Eastland, Fisher, Glasscock and 15 more	2 hr

Nearby

Mesoscale Discussions in Louisiana, 2013 Mesoscale Discussions in Texas, 2013 Every mesoscale discussion in 2013

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.