Alert archive / Louisiana / Mesoscale Discussions in 2006

Mesoscale Discussion 694

April 29, 20064 states

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2006, 11:55 AM CDT for 4 states. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued
Apr 29, 2006, 11:55 AM CDT (16:55 UTC)
Expired
Apr 29, 2006, 1:00 PM CDT
In force
65 min
Issued by
the Storm Prediction Center
All 69 counties

Columbia County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Sevier County, AR, Union County, AR, Acadia Parish, LA, Allen Parish, LA, Avoyelles Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, Concordia Parish, LA, De Soto Parish, LA, Evangeline Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Pointe Coupee 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 Feliciana Parish, LA, Winn Parish, LA, Adams County, MS, Wilkinson County, MS, Bowie County, TX, Camp County, TX, Cass County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Jasper County, TX, Jefferson County, TX, Marion County, TX, Morris County, TX, Newton County, TX, Orange County, TX, Panola County, TX, Red River County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX, Titus County, TX, Tyler County, TX, Upshur County, TX

The radar

The Shreveport radar (KSHV), 69 km from the middle of the area, began a volume at 16:59 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, 4.9 hours before the alert went out and 68 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 2006-04-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 187 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 2006-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 450 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
187 J/kg
Mixed-layer CIN
-88 J/kg
Mixed-layer LCL
486 m above ground
0-6 km bulk shear
72 kt
0-1 km storm-relative helicity
450 m²/s²
0-3 km storm-relative helicity
573 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.6

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
Apr 28, 11:08 PM CDTTornado WatchSPCHoward, Little River, Miller, Sevier7 hr
Apr 29, 4:03 AM CDTMesoscale DiscussionSPCHoward, Little River, Miller, Sevier57 min
Apr 29, 6:04 AM CDTTornado WatchSPCColumbia, Lafayette, Little River, Miller, Union7 hr
Apr 29, 7:37 AM CDTMesoscale DiscussionSPCColumbia, Lafayette, Little River, Miller, Union83 min
Apr 29, 12:47 PM CDTTornado WatchSPCBradley, Calhoun, Clark, Cleveland, Columbia, Conway and 31 more8 hr
Apr 29, 2:34 PM CDTMesoscale DiscussionSPCClark, Columbia, Crawford, Franklin, Garland, Hempstead and 17 more86 min
Apr 29, 6:26 PM CDTMesoscale DiscussionSPCBradley, Calhoun, Cleburne, Cleveland, Conway, Dallas and 12 more94 min
Apr 29, 9:57 AM CDTMesoscale DiscussionSPCAllen, Beauregard, Bienville, Calcasieu, Grant, Jackson and 7 more2 hr
Apr 29, 5:43 PM CDTTornado WatchSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberville, Jefferson and 16 more6 hr
Apr 28, 7:43 PM CDTTornado WatchSPCBandera, Bastrop, Bexar, Blanco, Burnet, Caldwell and 33 more6 hr
Apr 28, 8:44 PM CDTMesoscale DiscussionSPCClay, Collin, Cooke, Denton, Fannin, Grayson and 8 more91 min
Apr 28, 10:03 PM CDTMesoscale DiscussionSPCAnderson, Bastrop, Brazos, Burleson, Camp, Cass and 32 more87 min
Apr 28, 11:14 PM CDTMesoscale DiscussionSPCBandera, Bexar, Edwards, Frio, Kendall, Kerr and 5 more91 min
Apr 29, 1:51 AM CDTMesoscale DiscussionSPCAtascosa, Austin, Bastrop, Bell, Bexar, Brazos and 24 more24 min
Apr 29, 1:58 AM CDTTornado WatchSPCAtascosa, Bandera, Bastrop, Bell, Bexar, Blanco and 18 more3 hr
Apr 29, 10:05 AM CDTMesoscale DiscussionSPCCollin, Cooke, Delta, Fannin, Grayson, Hunt and 2 more115 min

Nearby

Mesoscale Discussions in Louisiana, 2006Mesoscale Discussions in Texas, 2006Mesoscale Discussions in Arkansas, 2006Every mesoscale discussion in 2006

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.