Alert archive / Louisiana / Mesoscale Discussions in 2009

Mesoscale Discussion 96

February 11, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Feb 11, 2009, 4:01 AM CST for 4 states. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued
Feb 11, 2009, 4:01 AM CST (10:01 UTC)
Expired
Feb 11, 2009, 5:30 AM CST
In force
89 min
Issued by
the Storm Prediction Center
All 62 counties

Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Lincoln County, AR, Ouachita County, AR, Union County, AR, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, East Carroll Parish, LA, Evangeline 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, Saint Landry Parish, LA, Tensas Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Adams County, MS, Bolivar County, MS, Claiborne County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Sharkey County, MS, Sunflower County, MS, Warren County, MS, Washington County, MS, Hardin County, TX, Jasper County, TX, Newton County, TX, Polk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Tyler County, TX

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 10.0 hours before the alert went out and 114 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 2009-02-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 367 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 2009-02-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 410 square meters per square second.1939587897117136Sfc1 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
367 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
785 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
410 m²/s²
0-3 km storm-relative helicity
547 m²/s²
Significant tornado parameter
0.7
Supercell composite
10.5

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
Feb 10, 6:13 PM CSTMesoscale DiscussionSPCCrawford, Washington92 min
Feb 10, 8:34 PM CSTMesoscale DiscussionSPCConway, Crawford, Faulkner, Franklin, Garland, Hempstead and 19 more86 min
Feb 10, 9:30 PM CSTTornado WatchSPCBaxter, Benton, Boone, Carroll, Clark, Cleburne and 42 more7 hr
Feb 10, 11:13 PM CSTMesoscale DiscussionSPCBaxter, Boone, Cleburne, Conway, Faulkner, Fulton and 18 more92 min
Feb 10, 11:45 PM CSTTornado WatchSPCArkansas, Clay, Craighead, Crittenden, Cross, Greene and 12 more6 hr
Feb 11, 12:37 AM CSTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Cleveland, Desha and 3 more53 min
Feb 11, 1:04 AM CSTTornado WatchSPCAshley, Bradley, Calhoun, Chicot, Cleveland, Desha and 3 more5 hr
Feb 11, 2:30 AM CSTMesoscale DiscussionSPCArkansas, Clay, Craighead, Crittenden, Cross, Fulton and 18 more90 min
Feb 11, 5:26 AM CSTMesoscale DiscussionSPCMississippi64 min
Feb 11, 9:36 AM CSTMesoscale DiscussionSPCGeorge, Greene, Harrison, Jackson84 min
Feb 10, 7:18 PM CSTMesoscale DiscussionSPCBrown, Comanche, Eastland, Erath, Jack, McCulloch and 4 more57 min
Feb 10, 9:46 PM CSTMesoscale DiscussionSPCAustin, Brazoria, Calhoun, Chambers, Colorado, DeWitt and 13 more29 min
Feb 10, 9:57 PM CSTSevere Thunderstorm WatchSPCAransas, Austin, Bastrop, Bee, Brazoria, Caldwell and 25 more5 hr

Nearby

Mesoscale Discussions in Louisiana, 2009Mesoscale Discussions in Arkansas, 2009Mesoscale Discussions in Mississippi, 2009Every mesoscale discussion in 2009

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.