Alert archive / Louisiana / Mesoscale Discussions in 2015

Mesoscale Discussion 1968

November 17, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Nov 17, 2015, 12:19 PM CST for 4 states. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued: Nov 17, 2015, 12:19 PM CST (18:19 UTC)
Expired: Nov 17, 2015, 2:15 PM CST
In force: 116 min
Issued by: the Storm Prediction Center

All 80 counties

Ashley County, AR, Chicot County, AR, Acadia Parish, LA, Allen Parish, LA, Ascension Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Catahoula Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Livingston Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Pointe Coupee Parish, LA, Rapides Parish, LA, Richland Parish, LA, Sabine Parish, LA, Saint Helena Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, Union Parish, LA, Vermilion Parish, LA, Vernon Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Jefferson Davis County, MS, Lawrence County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Walthall County, MS, Warren County, MS, Washington County, MS, Wilkinson County, MS, Yazoo County, MS, Hardin County, TX, Jasper County, TX, Jefferson County, TX, Newton County, TX, Orange County, TX, Sabine County, TX

The radar

The Ft Polk radar (KPOE), 54 km from the middle of the area, began a volume at 18:18 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 6.3 hours before the alert went out and 145 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: 1295 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 475 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 230 m²/s²
0-3 km storm-relative helicity: 307 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 7.5

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
Nov 17, 4:35 AM CST	Mesoscale Discussion	SPC	Benton, Crawford, Franklin, Howard, Johnson, Logan and 9 more	115 min
Nov 17, 4:48 AM CST	Tornado Watch	SPC	Howard, Little River, Miller, Sevier	4 hr
Nov 17, 6:27 AM CST	Severe Thunderstorm Watch	SPC	Baxter, Benton, Boone, Carroll, Clark, Conway and 21 more	6 hr
Nov 17, 8:24 AM CST	Mesoscale Discussion	SPC	Columbia, Lafayette	66 min
Nov 17, 8:55 AM CST	Tornado Watch	SPC	Columbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more	7 hr
Nov 17, 9:59 AM CST	Mesoscale Discussion	SPC	Arkansas, Ashley, Baxter, Boone, Bradley, Calhoun and 58 more	2 hr
Nov 17, 11:07 AM CST	Tornado Watch	SPC	Arkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 21 more	6 hr
Nov 17, 12:36 PM CST	Tornado Watch	SPC	Ashley, Chicot	7 hr
Nov 17, 1:35 PM CST	Mesoscale Discussion	SPC	Arkansas, Cleburne, Cleveland, Craighead, Crittenden, Cross and 25 more	115 min
Nov 17, 3:15 PM CST	Tornado Watch	SPC	Craighead, Crittenden, Cross, Lee, Mississippi, Phillips and 2 more	4 hr
Nov 17, 3:19 PM CST	Mesoscale Discussion	SPC	Clay, Fulton, Greene, Izard, Lawrence, Randolph and 1 more	116 min
Nov 17, 5:36 PM CST	Mesoscale Discussion	SPC	Crittenden, Cross, Lee, Monroe, Phillips, Poinsett and 1 more	84 min
Nov 17, 2:51 PM CST	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 20 more	84 min
Nov 17, 3:33 PM CST	Tornado Watch	SPC	Acadia, Allen, Avoyelles, Calcasieu, Cameron, Evangeline and 6 more	4 hr
Nov 17, 5:54 PM CST	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Calcasieu, Cameron, Evangeline and 6 more	96 min
Nov 16, 6:10 PM CST	Tornado Watch	SPC	Andrews, Borden, Coke, Crane, Crockett, Dawson and 22 more	8 hr
Nov 16, 8:07 PM CST	Mesoscale Discussion	SPC	Armstrong, Borden, Briscoe, Carson, Castro, Childress and 38 more	83 min
Nov 16, 8:16 PM CST	Mesoscale Discussion	SPC	Andrews, Borden, Coke, Crane, Crockett, Dawson and 26 more	89 min
Nov 16, 8:17 PM CST	Tornado Watch	SPC	Archer, Armstrong, Baylor, Briscoe, Carson, Childress and 31 more	7 hr
Nov 16, 10:19 PM CST	Mesoscale Discussion	SPC	Archer, Baylor, Callahan, Clay, Coke, Coleman and 16 more	86 min
Nov 16, 10:45 PM CST	Tornado Watch	SPC	Bosque, Brown, Callahan, Coleman, Collin, Comanche and 33 more	7 hr
Nov 17, 12:58 AM CST	Mesoscale Discussion	SPC	Archer, Clay, Cooke, Montague, Wichita	2 hr
Nov 17, 2:17 AM CST	Mesoscale Discussion	SPC	Bosque, Brown, Collin, Comanche, Cooke, Coryell and 21 more	118 min
Nov 17, 4:18 AM CST	Mesoscale Discussion	SPC	Anderson, Bell, Bosque, Bowie, Brazos, Camp and 39 more	57 min
Nov 17, 3:43 PM CST	Mesoscale Discussion	SPC	Dallam, Sherman	4 hr

Nearby

Mesoscale Discussions in Louisiana, 2015 Mesoscale Discussions in Mississippi, 2015 Mesoscale Discussions in Texas, 2015 Every mesoscale discussion in 2015

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.