Alert archive / Louisiana / Mesoscale Discussions in 2004

Mesoscale Discussion 290

April 7, 200411 parishes in Louisiana; 7 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 7, 2004, 11:43 PM CDT for 11 parishes in Louisiana; 7 counties in Mississippi. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued: Apr 7, 2004, 11:43 PM CDT (04:43 UTC)
Expired: Apr 8, 2004, 12:45 AM CDT
In force: 62 min
Issued by: the Storm Prediction Center

Counties Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Saint Landry Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Copiah County, MS, Franklin County, MS, Jefferson County, MS, Lincoln County, MS, Wilkinson County, MS

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 4.7 hours before the alert went out and 134 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: 825 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 1551 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 95 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.4

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 7, 7:20 PM CDT	Severe Thunderstorm Watch	SPC	Allen, Beauregard, Bienville, Caldwell, Catahoula, Claiborne and 18 more	6 hr
Apr 7, 9:59 PM CDT	Mesoscale Discussion	SPC	Allen, Avoyelles, Beauregard, Caldwell, Catahoula, Concordia and 15 more	61 min
Apr 7, 8:22 PM CDT	Mesoscale Discussion	SPC	Attala, Bolivar, Carroll, Choctaw, Clay, Grenada and 21 more	53 min

Nearby

Mesoscale Discussions in Louisiana, 2004 Mesoscale Discussions in Mississippi, 2004 Every mesoscale discussion in 2004

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.