Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 2034

December 23, 201516 counties in Arkansas; 9 parishes in Louisiana; 17 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Dec 23, 2015, 10:12 AM CST for 16 counties in Arkansas; 9 parishes in Louisiana; 17 counties in Texas. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Dec 23, 2015, 10:12 AM CST (16:12 UTC)
Expired: Dec 23, 2015, 11:45 AM CST
In force: 93 min
Issued by: the Storm Prediction Center

All 42 counties

Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Drew County, AR, Hempstead County, AR, Lafayette County, AR, Lincoln County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Pike County, AR, Union County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Lincoln Parish, LA, Red River Parish, LA, Union Parish, LA, Webster Parish, LA, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Morris County, TX, Nacogdoches County, TX, Panola County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Upshur County, TX

The radar

The Shreveport radar (KSHV), 42 km from the middle of the area, began a volume at 16:14 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 559Dec 23, 11:55 AM CST

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 4.2 hours before the alert went out and 43 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: 1041 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 598 m above ground
0-6 km bulk shear: 65 kt
0-1 km storm-relative helicity: 293 m²/s²
0-3 km storm-relative helicity: 218 m²/s²
Significant tornado parameter: 1.5
Supercell composite: 6.2

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 22, 10:17 PM CST	Mesoscale Discussion	SPC	Clark, Columbia, Dallas, Garland, Hempstead, Hot Spring and 9 more	2 hr
Dec 23, 12:06 AM CST	Tornado Watch	SPC	Bradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 10 more	7 hr
Dec 23, 4:39 AM CST	Mesoscale Discussion	SPC	Bradley, Calhoun, Clark, Cleburne, Cleveland, Columbia and 37 more	2 hr
Dec 23, 6:13 AM CST	Mesoscale Discussion	SPC	Clay, Greene, Randolph	2 hr
Dec 23, 6:20 AM CST	Tornado Watch	SPC	Arkansas, Baxter, Boone, Bradley, Calhoun, Clark and 50 more	7 hr
Dec 23, 9:05 AM CST	Mesoscale Discussion	SPC	Arkansas, Clark, Clay, Cleburne, Cleveland, Craighead and 28 more	85 min
Dec 23, 9:13 AM CST	Tornado Watch	SPC	Clay, Craighead, Greene, Lawrence, Mississippi, Poinsett and 1 more	8 hr
Dec 23, 10:29 AM CST	Mesoscale Discussion	SPC	Clay	91 min
Dec 23, 10:58 AM CST	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Chicot, Cleveland, Crittenden and 11 more	2 hr
Dec 23, 11:57 AM CST	Tornado Watch PDS	SPC	Arkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 12 more	9 hr
Dec 23, 12:48 PM CST	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 16 more	57 min
Dec 23, 2:49 PM CST	Mesoscale Discussion	SPC	Chicot, Crittenden, Cross, Desha, Lee, Mississippi and 2 more	86 min
Dec 22, 11:20 PM CST	Mesoscale Discussion	SPC	Jefferson, Lafourche, Plaquemines, St. Mary, Terrebonne	115 min
Dec 23, 2:34 AM CST	Mesoscale Discussion	SPC	Acadia, Allen, Ascension, Assumption, Avoyelles, Caldwell and 38 more	86 min
Dec 23, 1:33 PM CST	Mesoscale Discussion	SPC	East Baton Rouge, East Feliciana, Saint Helena, Washington	57 min

Nearby

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