Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 772

May 25, 20154 parishes in Louisiana; 20 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 25, 2015, 6:06 PM CDT for 4 parishes in Louisiana; 20 counties in Texas. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued: May 25, 2015, 6:06 PM CDT (23:06 UTC)
Expired: May 25, 2015, 7:00 PM CDT
In force: 54 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 24 counties

Allen Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Austin County, TX, Brazoria County, TX, Chambers County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Hardin County, TX, Harris County, TX, Jackson County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Tyler County, TX, Victoria County, TX, Waller County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 24 km from the middle of the area, began a volume at 23:05 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 216May 25, 6:20 PM CDT

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 11.1 hours before the alert went out and 193 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: 983 J/kg
Mixed-layer CIN: -106 J/kg
Mixed-layer LCL: 977 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 120 m²/s²
0-3 km storm-relative helicity: 123 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 3.6

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	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 18 more	93 min
May 25, 2:38 AM CDT	Mesoscale Discussion	SPC	Orleans, Saint Tammany, Washington	3 hr
May 25, 5:15 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	90 min
May 25, 5:51 PM CDT	Tornado Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	6 hr
May 25, 6:24 PM CDT	Tornado Watch	SPC	Acadia, Allen, Beauregard, Calcasieu, Cameron, Evangeline and 3 more	9 hr
May 24, 7:57 PM CDT	Mesoscale Discussion	SPC	Hemphill, Lipscomb, Ochiltree, Roberts	93 min
May 24, 8:24 PM CDT	Tornado Watch	SPC	Hansford, Lipscomb, Ochiltree	5 hr
May 25, 3:17 AM CDT	Mesoscale Discussion	SPC	Bandera, Coke, Crane, Crockett, Ector, Edwards and 21 more	4 hr
May 25, 6:45 AM CDT	Severe Thunderstorm Watch	SPC	Andrews, Borden, Brown, Callahan, Coke, Coleman and 34 more	6 hr
May 25, 6:50 AM CDT	Mesoscale Discussion	SPC	Andrews, Borden, Callahan, Coke, Coleman, Crosby and 26 more	55 min
May 25, 7:53 AM CDT	Mesoscale Discussion	SPC	Bandera, Bexar, Blanco, Burnet, Comal, Frio and 8 more	2 hr
May 25, 9:02 AM CDT	Tornado Watch	SPC	Atascosa, Bandera, Bastrop, Bexar, Blanco, Burnet and 27 more	7 hr
May 25, 10:13 AM CDT	Mesoscale Discussion	SPC	Anderson, Archer, Baylor, Bell, Bosque, Brown and 69 more	2 hr
May 25, 10:54 AM CDT	Tornado Watch	SPC	Archer, Baylor, Bell, Bosque, Brown, Callahan and 55 more	7 hr
May 25, 11:37 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bastrop, Bexar, Blanco, Burnet and 26 more	113 min
May 25, 1:54 PM CDT	Mesoscale Discussion	SPC	Bell, Bosque, Clay, Collin, Cooke, Coryell and 26 more	2 hr
May 25, 2:10 PM CDT	Mesoscale Discussion	SPC	Austin, Bastrop, Bexar, Blanco, Brazos, Burleson and 26 more	95 min
May 25, 2:35 PM CDT	Mesoscale Discussion	SPC	Anderson, Austin, Bowie, Brazos, Burleson, Camp and 34 more	55 min
May 25, 2:52 PM CDT	Tornado Watch	SPC	Anderson, Angelina, Bastrop, Blanco, Bowie, Brazos and 53 more	8 hr
May 25, 3:19 PM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Dimmit, Edwards, Frio and 9 more	56 min

Nearby

Mesoscale Discussions in Texas, 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.