Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 775

May 25, 201523 parishes in Louisiana; 28 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 25, 2015, 8:05 PM CDT for 23 parishes in Louisiana; 28 counties in Texas. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued
May 25, 2015, 8:05 PM CDT (01:05 UTC)
Expired
May 25, 2015, 9:30 PM CDT
In force
85 min
Issued by
the Storm Prediction Center
All 51 counties

Acadia Parish, LA, Allen Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Evangeline Parish, LA, Grant Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Rapides Parish, LA, Red River Parish, LA, Sabine Parish, LA, Saint Landry Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA, Angelina County, TX, Austin County, TX, Brazoria County, TX, Chambers County, TX, Colorado County, TX, DeWitt County, TX, Fort Bend County, TX, Goliad County, TX, Hardin County, TX, Harris County, TX, Jackson County, TX, Jasper County, TX, Jefferson County, TX, Lavaca County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Polk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Tyler County, TX, Victoria County, TX, Waller County, TX, Wharton County, TX

The radar

The Lake Charles radar (KLCH), 132 km from the middle of the area, began a volume at 01:08 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 00:00Z, 1.1 hours before the alert went out and 133 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-pSkew-T log-p diagram, Lake Charles Mun, LA at 00:00Z on 2015-05-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3112 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 00:00Z on 2015-05-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
3112 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
820 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
184 m²/s²
Significant tornado parameter
2.7
Supercell composite
16.2

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.

IssuedProductOfficeCountiesLasted
May 25, 10:14 PM CDTMesoscale DiscussionSPCAcadia, Ascension, Assumption, Avoyelles, Catahoula, Concordia and 22 more91 min
May 25, 10:37 PM CDTTornado WatchSPCAscension, Assumption, Avoyelles, Catahoula, Concordia, East Baton Rouge and 32 more6 hr
May 25, 11:13 PM CDTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, Cameron, Evangeline, Jefferson Davis and 1 more92 min
May 25, 11:57 PM CDTMesoscale DiscussionSPCAcadia, Ascension, Assumption, Avoyelles, Concordia, East Baton Rouge and 27 more93 min
May 26, 3:50 AM CDTMesoscale DiscussionSPCJefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 4 more85 min
May 26, 6:22 PM CDTMesoscale DiscussionSPCBienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 15 more83 min
May 26, 1:35 PM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Coke, Coleman and 21 more85 min
May 26, 2:53 PM CDTTornado WatchSPCArcher, Baylor, Callahan, Clay, Comanche, Eastland and 22 more7 hr
May 26, 3:54 PM CDTMesoscale DiscussionSPCCoke, Crockett, Irion, Reagan, Schleicher, Sterling and 4 more66 min
May 26, 5:23 PM CDTSevere Thunderstorm WatchSPCBrown, Coke, Coleman, Concho, Crockett, Glasscock and 14 more4 hr
May 26, 5:42 PM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Eastland, Erath and 14 more93 min

Nearby

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