Alert archive / Louisiana / Mesoscale Discussions in 2003

Mesoscale Discussion 242

March 13, 200311 parishes in Louisiana; Hancock County, Mississippi

The Storm Prediction Center issued this mesoscale discussion at Mar 13, 2003, 1:26 PM CST for 11 parishes in Louisiana; Hancock County, Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Mar 13, 2003, 1:26 PM CST (19:26 UTC)
Expired: Mar 13, 2003, 3:30 PM CST
In force: 2 hr
Issued by: the Storm Prediction Center

Counties Ascension Parish, LA, Assumption Parish, LA, Jefferson Parish, LA, Lafourche Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Saint Charles Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Hancock County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 7.4 hours before the alert went out and 72 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: 797 J/kg
Mixed-layer CIN: -157 J/kg
Mixed-layer LCL: 711 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 209 m²/s²
0-3 km storm-relative helicity: 247 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.0

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 13, 7:52 AM CST	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Cameron and 8 more	113 min
Mar 13, 8:30 AM CST	Severe Thunderstorm Watch	SPC	Acadia, Allen, Beauregard, Calcasieu, Cameron, Evangeline and 7 more	6 hr
Mar 13, 8:50 AM CST	Severe Thunderstorm Watch	SPC	Avoyelles, Catahoula, Concordia, East Carroll, Franklin, Madison and 1 more	5 hr
Mar 13, 10:45 AM CST	Severe Thunderstorm Watch	SPC	Ascension, Assumption, East Baton Rouge, Iberia, Iberville, Jefferson and 12 more	5 hr
Mar 13, 10:53 AM CST	Mesoscale Discussion	SPC	Acadia, Allen, Beauregard, Calcasieu, Cameron, Evangeline and 5 more	2 hr
Mar 13, 11:29 AM CST	Mesoscale Discussion	SPC	Catahoula, Concordia, East Carroll, Madison, Tensas	2 hr
Mar 13, 2:15 PM CST	Mesoscale Discussion	SPC	Jefferson, Orleans, Plaquemines, Saint Bernard	2 hr
Mar 13, 3:53 PM CST	Mesoscale Discussion	SPC	Beauregard, Calcasieu	2 hr
Mar 13, 9:39 AM CST	Mesoscale Discussion	SPC	Clarke, Forrest, George, Greene, Hancock, Harrison and 11 more	2 hr
Mar 13, 10:10 AM CST	Severe Thunderstorm Watch	SPC	Clarke, Forrest, George, Greene, Jasper, Jones and 6 more	6 hr
Mar 13, 12:59 PM CST	Mesoscale Discussion	SPC	Clarke, Greene, Jones, Kemper, Lauderdale, Noxubee and 2 more	2 hr
Mar 13, 3:10 PM CST	Severe Thunderstorm Watch	SPC	George, Greene, Harrison, Jackson, Pearl River, Perry and 1 more	5 hr

Nearby

Mesoscale Discussions in Louisiana, 2003 Mesoscale Discussions in Mississippi, 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.