Alert archive / Louisiana / Mesoscale Discussions in 2015

Mesoscale Discussion 2086

December 27, 201513 counties in Arkansas; 26 parishes in Louisiana; 14 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Dec 27, 2015, 2:27 PM CST for 13 counties in Arkansas; 26 parishes in Louisiana; 14 counties in Texas. It was in force for 63 min.

The area

The outline as issued.

The facts

Issued: Dec 27, 2015, 2:27 PM CST (20:27 UTC)
Expired: Dec 27, 2015, 3:30 PM CST
In force: 63 min
Issued by: the Storm Prediction Center
Chance of a watch: 95%

All 53 counties

Ashley County, AR, Bradley County, AR, Calhoun County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Drew County, AR, Hempstead County, AR, Lafayette County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Union County, AR, Allen Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Cameron Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Grant Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA, Bowie County, TX, Cass County, TX, Harrison County, TX, Jasper County, TX, Jefferson County, TX, Marion County, TX, Morris County, TX, Newton County, TX, Orange County, TX, Panola County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Tyler County, TX

The radar

The Ft Polk radar (KPOE), 48 km from the middle of the area, began a volume at 20:28 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.

Tornado Watch 572Dec 27, 2:40 PM CST

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 8.5 hours before the alert went out and 116 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: 625 J/kg
Mixed-layer CIN: -20 J/kg
Mixed-layer LCL: 707 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 350 m²/s²
0-3 km storm-relative helicity: 426 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 8.3

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
Dec 26, 7:32 PM CST	Mesoscale Discussion	SPC	Crawford, Sebastian	88 min
Dec 26, 11:27 PM CST	Mesoscale Discussion	SPC	Boone, Crawford, Franklin, Johnson, Logan, Madison and 8 more	2 hr
Dec 27, 5:44 AM CST	Mesoscale Discussion	SPC	Little River, Sevier	3 hr
Dec 27, 8:56 AM CST	Tornado Watch	SPC	Hempstead, Howard, Lafayette, Little River, Miller, Sevier	10 hr
Dec 27, 12:45 PM CST	Mesoscale Discussion	SPC	Hempstead, Howard, Lafayette, Little River, Miller, Sevier	2 hr
Dec 27, 12:47 PM CST	Mesoscale Discussion	SPC	Ashley, Bradley, Calhoun, Cleveland, Columbia, Drew and 2 more	88 min
Dec 27, 2:47 PM CST	Tornado Watch	SPC	Arkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 15 more	7 hr
Dec 27, 4:55 PM CST	Mesoscale Discussion	SPC	Ashley, Bradley, Calhoun, Cleveland, Columbia, Dallas and 8 more	2 hr
Dec 27, 3:15 PM CST	Mesoscale Discussion	SPC	East Carroll, East Feliciana, Madison, Saint Helena, Tensas, Washington	90 min
Dec 26, 8:09 PM CST	Mesoscale Discussion	SPC	Borden, Callahan, Coke, Coleman, Concho, Crockett and 21 more	2 hr
Dec 26, 8:58 PM CST	Severe Thunderstorm Watch	SPC	Bandera, Crockett, Edwards, Gillespie, Kerr, Kimble and 11 more	7 hr
Dec 26, 11:21 PM CST	Mesoscale Discussion	SPC	Armstrong, Bailey, Briscoe, Carson, Castro, Cochran and 17 more	5 hr
Dec 26, 11:48 PM CST	Mesoscale Discussion	SPC	Concho, Edwards, Gillespie, Kerr, Kimble, Kinney and 11 more	87 min
Dec 27, 3:38 AM CST	Mesoscale Discussion	SPC	Hardeman	6 hr
Dec 27, 4:36 AM CST	Mesoscale Discussion	SPC	Carson, Dallam, Deaf Smith, Gray, Hansford, Hartley and 11 more	6 hr
Dec 27, 5:15 AM CST	Mesoscale Discussion	SPC	Andrews, Cochran, Crane, Culberson, Ector, Gaines and 10 more	5 hr
Dec 27, 9:50 AM CST	Mesoscale Discussion	SPC	Baylor, Childress, Coke, Cottle, Crockett, Dickens and 25 more	6 hr
Dec 27, 11:24 AM CST	Mesoscale Discussion	SPC	Andrews, Bailey, Borden, Castro, Cochran, Crane and 24 more	6 hr
Dec 27, 12:04 PM CST	Mesoscale Discussion	SPC	Archer, Bosque, Clay, Collin, Comanche, Cooke and 24 more	2 hr
Dec 27, 3:19 PM CST	Mesoscale Discussion	SPC	Brazoria, Chambers, Fort Bend, Galveston, Harris, Houston and 7 more	116 min
Dec 27, 3:55 PM CST	Mesoscale Discussion	SPC	Archer, Baylor, Callahan, Childress, Coke, Coleman and 31 more	4 hr

Nearby

Mesoscale Discussions in Louisiana, 2015 Mesoscale Discussions in Texas, 2015 Mesoscale Discussions in Arkansas, 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.