Alert archive / Texas / Mesoscale Discussions in 2011

Mesoscale Discussion 602

April 26, 20115 counties in Arkansas; 19 parishes in Louisiana; 70 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2011, 6:43 PM CDT for 5 counties in Arkansas; 19 parishes in Louisiana; 70 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 26, 2011, 6:43 PM CDT (23:43 UTC)
Expired
Apr 26, 2011, 8:45 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 94 counties

Columbia County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Union County, AR, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Grant Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Rapides Parish, LA, Red River Parish, LA, Sabine Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, Winn Parish, LA, Anderson County, TX, Angelina County, TX, Austin County, TX, Bastrop County, TX, Bell County, TX, Bowie County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Comal County, TX, Coryell County, TX, Delta County, TX, Ellis County, TX, Falls County, TX, Fayette County, TX, Franklin County, TX, Freestone County, TX, Gregg County, TX, Grimes County, TX, Guadalupe County, TX, Hardin County, TX, Harrison County, TX, Hays County, TX, Henderson County, TX, Hill County, TX, Hopkins County, TX, Houston County, TX, Hunt County, TX, Jasper County, TX, Kaufman County, TX, Lamar County, TX, Lee County, TX, Leon County, TX, Liberty County, TX, Limestone County, TX, Madison County, TX, Marion County, TX, McLennan County, TX, Milam County, TX, Montgomery County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Newton County, TX, Panola County, TX, Polk County, TX, Rains County, TX, Red River County, TX, Robertson County, TX, Rockwall County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Travis County, TX, Trinity County, TX, Tyler County, TX, Upshur County, TX, Van Zandt County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Williamson County, TX, Wood County, TX

The radar

The Ft Hood radar (KGRK), 167 km from the middle of the area, began a volume at 23:43 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

Fort Worth, TX (KFWD), launched 12:00Z, 11.7 hours before the alert went out and 213 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, Fort Worth, TX at 12:00Z on 2011-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Fort Worth, TX at 12:00Z on 2011-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 210 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
911 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
210 m²/s²
0-3 km storm-relative helicity
244 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
Apr 25, 7:34 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 33 more116 min
Apr 25, 9:23 PM CDTTornado WatchSPCAshley, Chicot7 hr
Apr 25, 11:05 PM CDTMesoscale DiscussionSPCAshley, Chicot115 min
Apr 26, 10:51 AM CDTMesoscale DiscussionSPCCrittenden, Cross, Lee, Mississippi, Phillips, Poinsett and 2 more54 min
Apr 26, 1:11 PM CDTMesoscale DiscussionSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 12 more2 hr
Apr 26, 1:44 PM CDTTornado Watch PDSSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 16 more10 hr
Apr 26, 2:41 PM CDTMesoscale DiscussionSPCArkansas, Chicot, Craighead, Crittenden, Cross, Desha and 11 more94 min
Apr 26, 3:02 PM CDTTornado Watch PDSSPCArkansas, Ashley, Chicot, Clay, Craighead, Crittenden and 21 more7 hr
Apr 26, 3:59 PM CDTMesoscale DiscussionSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 12 more91 min
Apr 26, 5:00 PM CDTMesoscale DiscussionSPCBaxter, Boone, Cleburne, Conway, Crawford, Faulkner and 19 more30 min
Apr 26, 5:08 PM CDTTornado WatchSPCBaxter, Cleburne, Conway, Crawford, Franklin, Fulton and 15 more5 hr
Apr 26, 6:17 PM CDTMesoscale DiscussionSPCArkansas, Baxter, Benton, Boone, Bradley, Calhoun and 63 more118 min
Apr 25, 9:37 PM CDTMesoscale DiscussionSPCDe Soto, Sabine83 min
Apr 25, 10:47 PM CDTTornado WatchSPCAllen, Beauregard, Evangeline, Rapides, Sabine, Vernon5 hr
Apr 26, 1:34 AM CDTMesoscale DiscussionSPCAllen, Beauregard, Calcasieu, Evangeline, Jefferson Davis, Rapides and 1 more86 min
Apr 26, 1:52 AM CDTSevere Thunderstorm WatchSPCAcadia, Allen, Avoyelles, Beauregard, Calcasieu, Cameron and 7 more5 hr
Apr 26, 4:56 PM CDTTornado WatchSPCBeauregard, Bienville, Caldwell, De Soto, Grant, Jackson and 9 more5 hr
Apr 26, 3:01 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bastrop, Bee, Bexar, Blanco and 22 more89 min
Apr 26, 3:15 PM CDTMesoscale DiscussionSPCArcher, Baylor, Childress, Clay, Collingsworth, Cottle and 16 more90 min
Apr 26, 3:43 PM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Clay, Foard, Hardeman, Knox and 2 more6 hr

Nearby

Mesoscale Discussions in Texas, 2011Mesoscale Discussions in Louisiana, 2011Mesoscale Discussions in Arkansas, 2011Every mesoscale discussion in 2011

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.