Alert archive / Texas / Mesoscale Discussions in 2013

Mesoscale Discussion 351

March 31, 20134 states

The Storm Prediction Center issued this mesoscale discussion at Mar 31, 2013, 7:36 AM CDT for 4 states. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued
Mar 31, 2013, 7:36 AM CDT (12:36 UTC)
Expired
Mar 31, 2013, 9:30 AM CDT
In force
114 min
Issued by
the Storm Prediction Center
All 59 counties

Columbia County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Sevier 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, Choctaw County, OK, McCurtain County, OK, Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Collin County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Freestone County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Hill County, TX, Hood County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Somervell County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 149 km from the middle of the area, began a volume at 12:38 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

Shreveport, LA (KSHV), launched 12:00Z, 0.6 hours before the alert went out and 155 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, Shreveport, LA at 12:00Z on 2013-03-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 252 joules per kilogram.LCLLFCEL10008507005003002001001 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, Shreveport, LA at 12:00Z on 2013-03-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 93 square meters per square second.19395878Sfc1 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
252 J/kg
Mixed-layer CIN
-155 J/kg
Mixed-layer LCL
700 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

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
Mar 30, 9:06 PM CDTSevere Thunderstorm WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more5 hr
Mar 30, 10:44 PM CDTMesoscale DiscussionSPCCrawford, Franklin, Johnson, Logan, Madison, Newton and 6 more91 min
Mar 31, 5:10 AM CDTSevere Thunderstorm WatchSPCHempstead, Howard, Lafayette, Little River, Miller, Sevier7 hr
Mar 31, 9:20 AM CDTSevere Thunderstorm WatchSPCColumbia, Union5 hr
Mar 31, 10:33 AM CDTMesoscale DiscussionSPCCalhoun, Columbia, Union57 min
Mar 31, 11:54 AM CDTMesoscale DiscussionSPCAllen, Avoyelles, Beauregard, Caldwell, Catahoula, Concordia and 20 more36 min
Mar 31, 12:17 PM CDTSevere Thunderstorm WatchSPCAcadia, Allen, Ascension, Avoyelles, Beauregard, Calcasieu and 32 more6 hr
Mar 31, 2:32 PM CDTMesoscale DiscussionSPCAllen, Avoyelles, Beauregard, Calcasieu, Caldwell, Catahoula and 21 more58 min
Mar 31, 2:48 PM CDTSevere Thunderstorm WatchSPCCameron, Iberia, Saint Martin, St. Mary, Vermilion5 hr
Mar 31, 3:21 PM CDTMesoscale DiscussionSPCJefferson, Orleans, Saint Charles, Saint James, Saint John the Baptist, Saint Tammany and 1 more54 min
Mar 31, 3:38 PM CDTSevere Thunderstorm WatchSPCAssumption, Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard and 5 more3 hr
Mar 30, 7:37 PM CDTMesoscale DiscussionSPCAdair, Cherokee, Craig, Creek, Delaware, McIntosh and 9 more53 min
Mar 30, 8:14 PM CDTMesoscale DiscussionSPCAtoka, Carter, Cleveland, Coal, Comanche, Cotton and 17 more91 min
Mar 31, 1:13 AM CDTMesoscale DiscussionSPCBeckham, Blaine, Caddo, Canadian, Carter, Cleveland and 23 more62 min
Mar 31, 4:54 AM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Coal, Comanche and 12 more96 min
Mar 31, 1:00 PM CDTMesoscale DiscussionSPCAustin, Bandera, Bastrop, Bexar, Blanco, Brazos and 32 more60 min
Mar 31, 1:17 PM CDTSevere Thunderstorm WatchSPCAtascosa, Austin, Bandera, Bastrop, Bell, Bexar and 47 more9 hr
Mar 31, 5:24 PM CDTMesoscale DiscussionSPCAtascosa, Brazoria, Chambers, DeWitt, Dimmit, Fort Bend and 18 more96 min
Mar 31, 6:20 PM CDTSevere Thunderstorm WatchSPCBee, Duval, Jim Wells, Kleberg, La Salle, Live Oak and 4 more4 hr

Nearby

Mesoscale Discussions in Texas, 2013Mesoscale Discussions in Louisiana, 2013Mesoscale Discussions in Arkansas, 2013Every mesoscale discussion in 2013

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.