Alert archive / Louisiana / Mesoscale Discussions in 2013

Mesoscale Discussion 193

February 21, 201310 parishes in Louisiana

The Storm Prediction Center issued this mesoscale discussion at Feb 21, 2013, 3:15 PM CST for 10 parishes in Louisiana. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Feb 21, 2013, 3:15 PM CST (21:15 UTC)
Expired: Feb 21, 2013, 4:45 PM CST
In force: 90 min
Issued by: the Storm Prediction Center

Counties Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Catahoula Parish, LA, Evangeline Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Rapides Parish, LA, Vernon Parish, LA, Winn Parish, LA

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 9.3 hours before the alert went out and 109 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: 13 J/kg
Mixed-layer CIN: -343 J/kg
Mixed-layer LCL: 461 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 509 m²/s²
0-3 km storm-relative helicity: 644 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.8

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
Feb 21, 1:22 PM CST	Mesoscale Discussion	SPC	Ascension, Assumption, Avoyelles, Concordia, East Baton Rouge, East Feliciana and 14 more	113 min
Feb 21, 1:37 PM CST	Tornado Watch	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 10 more	5 hr
Feb 21, 3:48 PM CST	Mesoscale Discussion	SPC	Concordia, Franklin, Saint Helena, Tensas, Washington	57 min

Nearby

Mesoscale Discussions in Louisiana, 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.