Alert archive / Louisiana / Mesoscale Discussions in 2016

Mesoscale Discussion 369

April 11, 20164 states

The Storm Prediction Center issued this mesoscale discussion at Apr 11, 2016, 6:09 PM CDT for 4 states. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued
Apr 11, 2016, 6:09 PM CDT (23:09 UTC)
Expired
Apr 11, 2016, 7:15 PM CDT
In force
66 min
Issued by
the Storm Prediction Center
All 59 counties

Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Columbia County, AR, Drew County, AR, Ouachita County, AR, Union County, AR, Avoyelles Parish, LA, Bienville Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, West Carroll Parish, LA, West Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Amite County, MS, Carroll County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Leflore County, MS, Madison County, MS, Montgomery County, MS, Sharkey County, MS, Sunflower County, MS, Warren County, MS, Washington County, MS, Wilkinson County, MS, Yazoo County, MS, Newton County, TX, Sabine County, TX

The radar

The Ft Polk radar (KPOE), 104 km from the middle of the area, began a volume at 23:08 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

Shreveport, LA (KBAD), launched 12:00Z, 11.2 hours before the alert went out and 135 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 2016-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 520 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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 2016-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 270 square meters per square second.1939587897Sfc1 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
520 J/kg
Mixed-layer CIN
-128 J/kg
Mixed-layer LCL
585 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
270 m²/s²
0-3 km storm-relative helicity
389 m²/s²
Significant tornado parameter
0.4
Supercell composite
4.2

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 11, 12:57 AM CDTSevere Thunderstorm WatchSPCCrawford, Sebastian, Washington4 hr
Apr 11, 11:48 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 15 more2 hr
Apr 11, 1:05 PM CDTSevere Thunderstorm WatchSPCAshley, Bradley, Calhoun, Chicot, Columbia, Desha and 5 more6 hr
Apr 11, 1:38 PM CDTSevere Thunderstorm WatchSPCHempstead, Howard, Little River, Miller, Polk, Sevier9 hr
Apr 11, 3:42 PM CDTMesoscale DiscussionSPCAshley, Bradley, Chicot, Columbia, Drew, Union93 min
Apr 11, 12:15 PM CDTMesoscale DiscussionSPCAllen, Avoyelles, Catahoula, Concordia, East Feliciana, Evangeline and 12 more3 hr
Apr 11, 6:58 PM CDTSevere Thunderstorm WatchSPCBienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 20 more5 hr
Apr 11, 6:40 PM CDTMesoscale DiscussionSPCClarke, Covington, Forrest, Greene, Jones, Lamar and 2 more65 min
Apr 10, 7:36 PM CDTMesoscale DiscussionSPCMontague114 min
Apr 10, 8:54 PM CDTMesoscale DiscussionSPCDimmit, Edwards, Kinney, Maverick, Real, Uvalde and 2 more66 min
Apr 10, 9:31 PM CDTMesoscale DiscussionSPCArcher, Baylor, Childress, Clay, Cooke, Cottle and 19 more59 min
Apr 10, 9:52 PM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Clay, Cooke, Foard, Hardeman and 4 more6 hr
Apr 10, 11:06 PM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bexar, Comal, Dimmit, Frio and 9 more54 min
Apr 11, 6:15 AM CDTMesoscale DiscussionSPCClay, Collin, Cooke, Delta, Denton, Fannin and 7 more3 hr
Apr 11, 12:39 PM CDTMesoscale DiscussionSPCArcher, Baylor, Camp, Clay, Collin, Cooke and 33 more2 hr
Apr 11, 1:43 PM CDTMesoscale DiscussionSPCAustin, Brazos, Grimes, Hardin, Harris, Liberty and 8 more3 hr
Apr 11, 3:26 PM CDTMesoscale DiscussionSPCClay, Collin, Cooke, Dallas, Delta, Denton and 18 more94 min
Apr 11, 4:49 PM CDTMesoscale DiscussionSPCCollin, Dallas, Denton, Hunt, Rains, Rockwall and 1 more86 min
Apr 11, 5:27 PM CDTMesoscale DiscussionSPCArcher, Baylor, Fisher, Haskell, Jones, King and 7 more93 min

Nearby

Mesoscale Discussions in Louisiana, 2016Mesoscale Discussions in Mississippi, 2016Mesoscale Discussions in Arkansas, 2016Every mesoscale discussion in 2016

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.