Alert archive / Louisiana / Mesoscale Discussions in 2014

Mesoscale Discussion 353

April 14, 20144 states

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2014, 3:36 PM CDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 14, 2014, 3:36 PM CDT (20:36 UTC)
Expired: Apr 14, 2014, 6:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 60%

All 30 counties

Baldwin County, AL, Conecuh County, AL, Covington County, AL, Escambia County, AL, Mobile County, AL, Escambia County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Ascension Parish, LA, Assumption Parish, LA, Jefferson Parish, LA, Lafourche Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Plaquemines Parish, LA, Saint Bernard Parish, LA, Saint Charles Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, St. Mary Parish, LA, Tangipahoa Parish, LA, Terrebonne Parish, LA, George County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Stone County, MS

The radar

The Mobile radar (KMOB), 55 km from the middle of the area, began a volume at 20:38 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 nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.6 hours before the alert went out and 149 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: 502 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 602 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 270 m²/s²
0-3 km storm-relative helicity: 375 m²/s²
Significant tornado parameter: 0.9
Supercell composite: 4.9

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 13, 7:54 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	66 min
Apr 13, 11:06 PM CDT	Severe Thunderstorm Watch	SPC	Bossier, Caddo, Claiborne, Webster	6 hr
Apr 14, 1:22 AM CDT	Mesoscale Discussion	SPC	East Carroll, Franklin, Madison, Morehouse, Ouachita, Richland and 2 more	53 min
Apr 14, 1:50 AM CDT	Tornado Watch	SPC	East Carroll, Franklin, Madison, Morehouse, Richland, Tensas and 1 more	5 hr
Apr 14, 2:05 AM CDT	Mesoscale Discussion	SPC	Bossier, Caddo, Claiborne, Webster	85 min
Apr 14, 4:34 AM CDT	Mesoscale Discussion	SPC	Franklin, Madison, Richland, Tensas	56 min
Apr 14, 7:42 AM CDT	Mesoscale Discussion	SPC	Beauregard, Natchitoches, Red River, Sabine, Vernon, Winn	2 hr
Apr 14, 10:34 AM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	6 hr
Apr 14, 12:30 PM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 25 more	2 hr
Apr 14, 1:11 PM CDT	Severe Thunderstorm Watch	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 41 more	10 hr
Apr 13, 10:33 PM CDT	Mesoscale Discussion	SPC	Bolivar, Coahoma, DeSoto, Tunica	57 min

Nearby

Mesoscale Discussions in Louisiana, 2014 Mesoscale Discussions in Mississippi, 2014 Mesoscale Discussions in Alabama, 2014 Every mesoscale discussion in 2014

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.