Alert archive / Louisiana / Mesoscale Discussions in 2012

Mesoscale Discussion 1134

June 12, 20124 states

The Storm Prediction Center issued this mesoscale discussion at Jun 12, 2012, 2:54 AM CDT for 4 states. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued
Jun 12, 2012, 2:54 AM CDT (07:54 UTC)
Expired
Jun 12, 2012, 4:30 AM CDT
In force
96 min
Issued by
the Storm Prediction Center
All 45 counties

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, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Tensas Parish, LA, Union Parish, LA, Webster Parish, LA, Winn Parish, LA, Adams County, MS, Bowie County, TX, Camp County, TX, Cass County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Morris County, TX, Panola County, TX, Upshur County, TX

The radar

The Shreveport radar (KSHV), 79 km from the middle of the area, began a volume at 07:57 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 00:00Z, 7.9 hours before the alert went out and 69 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 00:00Z on 2012-06-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2755 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 00:00Z on 2012-06-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -42 square meters per square second.1939Sfc1 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
2755 J/kg
Mixed-layer CIN
-66 J/kg
Mixed-layer LCL
1712 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
-42 m²/s²
0-3 km storm-relative helicity
76 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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
Jun 11, 7:33 PM CDTMesoscale DiscussionSPCAshley, Chicot, Drew57 min
Jun 11, 9:25 PM CDTSevere Thunderstorm WatchSPCSebastian7 hr
Jun 11, 11:52 PM CDTSevere Thunderstorm WatchSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 15 more6 hr
Jun 12, 3:21 AM CDTSevere Thunderstorm WatchSPCAshley, Chicot, Columbia, Hempstead, Lafayette, Little River and 3 more8 hr
Jun 12, 6:08 AM CDTMesoscale DiscussionSPCAshley, Chicot2 hr
Jun 11, 8:37 PM CDTSevere Thunderstorm WatchSPCCatahoula, Concordia, East Feliciana, Franklin, Saint Helena, Saint Tammany and 4 more4 hr
Jun 11, 10:51 PM CDTMesoscale DiscussionSPCEast Baton Rouge, East Feliciana, Saint Helena, Tangipahoa, Washington, West Baton Rouge and 1 more54 min
Jun 12, 7:11 AM CDTSevere Thunderstorm WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 32 more8 hr
Jun 12, 9:23 AM CDTMesoscale DiscussionSPCGrant, LaSalle, Natchitoches, Sabine67 min
Jun 12, 12:12 PM CDTMesoscale DiscussionSPCAcadia, Allen, Beauregard, Calcasieu, Cameron, Iberia and 5 more63 min
Jun 11, 7:11 PM CDTMesoscale DiscussionSPCBrown, Callahan, Clay, Coke, Coleman, Collin and 29 more94 min
Jun 11, 9:54 PM CDTMesoscale DiscussionSPCArcher, Baylor, Brown, Callahan, Clay, Coke and 31 more66 min
Jun 11, 11:29 PM CDTMesoscale DiscussionSPCGrayson61 min
Jun 12, 4:08 AM CDTMesoscale DiscussionSPCArmstrong, Bailey, Briscoe, Castro, Childress, Deaf Smith and 9 more2 hr
Jun 12, 10:32 AM CDTMesoscale DiscussionSPCArcher, Clay, Collin, Cooke, Dallas, Denton and 19 more88 min
Jun 12, 11:00 AM CDTSevere Thunderstorm WatchSPCAnderson, Bell, Bosque, Brown, Callahan, Collin and 36 more6 hr
Jun 12, 2:02 PM CDTMesoscale DiscussionSPCDallam, Deaf Smith, Hartley, Oldham88 min
Jun 12, 2:16 PM CDTSevere Thunderstorm WatchSPCDallam, Deaf Smith, Hartley, Oldham8 hr
Jun 12, 2:45 PM CDTMesoscale DiscussionSPCCoke, Coleman, Concho, Glasscock, Midland, Mitchell and 4 more60 min
Jun 12, 3:00 PM CDTMesoscale DiscussionSPCAndrews, Bailey, Cochran, Crane, Ector, Gaines and 7 more60 min
Jun 12, 3:28 PM CDTMesoscale DiscussionSPCAnderson, Bell, Bosque, Brazos, Brown, Burleson and 37 more62 min
Jun 12, 3:44 PM CDTSevere Thunderstorm WatchSPCAndrews, Bailey, Cochran, Crane, Culberson, Ector and 13 more8 hr
Jun 12, 3:56 PM CDTSevere Thunderstorm WatchSPCAnderson, Austin, Bell, Brazoria, Brazos, Burleson and 24 more4 hr
Jun 12, 5:42 PM CDTMesoscale DiscussionSPCDallam63 min

Nearby

Mesoscale Discussions in Louisiana, 2012Mesoscale Discussions in Arkansas, 2012Mesoscale Discussions in Texas, 2012Every mesoscale discussion in 2012

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.