Alert archive / Texas / Mesoscale Discussions in 2011

Mesoscale Discussion 958

May 25, 201115 counties in Arkansas; 4 parishes in Louisiana; 16 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 25, 2011, 1:53 PM CDT for 15 counties in Arkansas; 4 parishes in Louisiana; 16 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 25, 2011, 1:53 PM CDT (18:53 UTC)
Expired: May 25, 2011, 4:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 35 counties

Bradley County, AR, Calhoun County, AR, Clark County, AR, Columbia County, AR, Dallas County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Pike County, AR, Sevier County, AR, Union County, AR, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, Webster Parish, LA, Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Marion County, TX, Morris County, TX, Panola County, TX, Rusk County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 64 km from the middle of the area, began a volume at 18:59 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 374May 25, 3:20 PM CDT

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 6.9 hours before the alert went out and 65 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: 1799 J/kg
Mixed-layer CIN: -149 J/kg
Mixed-layer LCL: 925 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 383 m²/s²
0-3 km storm-relative helicity: 425 m²/s²
Significant tornado parameter: 1.5
Supercell composite: 19.5

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
May 24, 7:42 PM CDT	Mesoscale Discussion	SPC	Benton, Crawford, Little River, Polk, Scott, Sebastian and 2 more	63 min
May 24, 8:05 PM CDT	Tornado Watch	SPC	Baxter, Benton, Boone, Carroll, Clark, Conway and 30 more	7 hr
May 24, 11:24 PM CDT	Mesoscale Discussion	SPC	Baxter, Boone, Carroll, Clark, Conway, Franklin and 21 more	96 min
May 25, 12:48 AM CDT	Mesoscale Discussion	SPC	Clay, Craighead, Fulton, Greene, Independence, Jackson and 4 more	57 min
May 25, 7:31 AM CDT	Mesoscale Discussion	SPC	Clay, Craighead, Crittenden, Cross, Greene, Mississippi and 1 more	59 min
May 25, 9:54 AM CDT	Mesoscale Discussion	SPC	Baxter, Boone, Carroll, Clay, Cleburne, Conway and 33 more	96 min
May 25, 10:18 AM CDT	Mesoscale Discussion	SPC	Fulton, Independence, Izard, Jackson, St. Francis, Sharp and 2 more	57 min
May 25, 10:37 AM CDT	Tornado Watch	SPC	Baxter, Boone, Carroll, Fulton, Izard, Madison and 5 more	7 hr
May 25, 11:02 AM CDT	Mesoscale Discussion	SPC	Clay	28 min
May 25, 11:52 AM CDT	Mesoscale Discussion	SPC	Arkansas, Clark, Clay, Cleburne, Cleveland, Conway and 38 more	83 min
May 25, 12:28 PM CDT	Tornado Watch PDS	SPC	Arkansas, Baxter, Bradley, Calhoun, Clark, Clay and 41 more	8 hr
May 25, 2:56 PM CDT	Mesoscale Discussion	SPC	Arkansas, Calhoun, Clark, Clay, Cleburne, Cleveland and 33 more	94 min
May 25, 3:10 PM CDT	Mesoscale Discussion	SPC	Clay	95 min
May 25, 3:16 PM CDT	Tornado Watch	SPC	Ashley, Chicot, Columbia, Lafayette, Miller, Nevada and 1 more	7 hr
May 25, 5:56 PM CDT	Mesoscale Discussion	SPC	Arkansas, Craighead, Crittenden, Cross, Greene, Lee and 5 more	64 min
May 24, 11:00 PM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Burnet, Coryell, Falls, Freestone and 6 more	60 min
May 24, 11:22 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Coryell, Falls, Freestone, Henderson and 7 more	5 hr
May 25, 3:10 AM CDT	Mesoscale Discussion	SPC	Bastrop, Bell, Blanco, Brazos, Burleson, Burnet and 8 more	95 min
May 25, 5:15 PM CDT	Mesoscale Discussion	SPC	Anderson, Austin, Bastrop, Brazos, Burleson, Caldwell and 23 more	60 min

Nearby

Mesoscale Discussions in Texas, 2011 Mesoscale Discussions in Arkansas, 2011 Mesoscale Discussions in Louisiana, 2011 Every mesoscale discussion in 2011

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.