Alert archive / Mississippi / Mesoscale Discussions in 2013

Mesoscale Discussion 27

January 13, 201311 parishes in Louisiana; 14 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jan 13, 2013, 2:30 PM CST for 11 parishes in Louisiana; 14 counties in Mississippi. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Jan 13, 2013, 2:30 PM CST (20:30 UTC)
Expired: Jan 13, 2013, 4:00 PM CST
In force: 90 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 25 counties

Ascension Parish, LA, Assumption 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, Washington Parish, LA, Covington County, MS, Forrest County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jones County, MS, Lamar County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.5 hours before the alert went out and 44 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 795 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 276 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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
Jan 12, 6:18 PM CST	Mesoscale Discussion	SPC	Bossier, Claiborne, Union, Webster	117 min
Jan 12, 10:33 PM CST	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 14 more	87 min
Jan 12, 11:29 PM CST	Tornado Watch	SPC	Bienville, Caldwell, Catahoula, Claiborne, De Soto, East Carroll and 17 more	5 hr
Jan 13, 3:53 AM CST	Mesoscale Discussion	SPC	Bienville, Caldwell, Catahoula, Claiborne, Concordia, East Carroll and 16 more	97 min
Jan 13, 1:18 AM CST	Mesoscale Discussion	SPC	Bolivar, Coahoma	87 min
Jan 13, 2:46 PM CST	Mesoscale Discussion	SPC	Kemper, Lauderdale, Lowndes, Monroe, Neshoba, Newton and 1 more	119 min

Nearby

Mesoscale Discussions in Mississippi, 2013 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.