Alert archive / Texas / Mesoscale Discussions in 2011

Mesoscale Discussion 568

April 25, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2011, 10:46 AM CDT for 4 states. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued
Apr 25, 2011, 10:46 AM CDT (15:46 UTC)
Expired
Apr 25, 2011, 11:45 AM CDT
In force
59 min
Issued by
the Storm Prediction Center
All 67 counties

Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Sevier County, AR, Bossier Parish, LA, Caddo Parish, LA, De Soto Parish, LA, Atoka County, OK, Bryan County, OK, Choctaw County, OK, Coal County, OK, Johnston County, OK, Latimer County, OK, Marshall County, OK, McCurtain County, OK, Pittsburg County, OK, Pushmataha County, OK, Anderson County, TX, Bosque County, TX, Bowie County, TX, Brazos County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Collin County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Falls County, TX, Fannin County, TX, Franklin County, TX, Freestone County, TX, Grayson County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Hill County, TX, Hopkins County, TX, Houston County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Leon County, TX, Limestone County, TX, Madison County, TX, Marion County, TX, McLennan County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Rains County, TX, Red River County, TX, Robertson County, TX, Rockwall County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 125 km from the middle of the area, began a volume at 15:49 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, 3.8 hours before the alert went out and 120 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 2011-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2645 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, Fort Worth, TX at 12:00Z on 2011-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 346 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
2645 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
564 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
346 m²/s²
0-3 km storm-relative helicity
373 m²/s²
Significant tornado parameter
6.1
Supercell composite
21.8

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 24, 10:13 PM CDTMesoscale DiscussionSPCClark, Cleburne, Conway, Faulkner, Garland, Grant and 15 more2 hr
Apr 24, 11:43 PM CDTSevere Thunderstorm WatchSPCHempstead, Howard, Little River, Miller, Nevada, Sevier5 hr
Apr 25, 1:57 AM CDTMesoscale DiscussionSPCCleveland, Dallas, Jefferson, Lincoln63 min
Apr 25, 4:41 AM CDTSevere Thunderstorm WatchSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 25 more7 hr
Apr 25, 7:23 AM CDTMesoscale DiscussionSPCCalhoun, Clark, Cleveland, Columbia, Dallas, Garland and 11 more97 min
Apr 25, 8:37 AM CDTMesoscale DiscussionSPCArkansas, Cleveland, Crittenden, Desha, Drew, Jefferson and 7 more53 min
Apr 25, 9:17 AM CDTSevere Thunderstorm WatchSPCCrittenden, Lee, Phillips, St. Francis6 hr
Apr 25, 11:00 AM CDTTornado WatchSPCCarroll, Clark, Crawford, Franklin, Hempstead, Howard and 13 more7 hr
Apr 25, 1:15 PM CDTMesoscale DiscussionSPCCrittenden, Cross, Lee, Phillips, St. Francis60 min
Apr 25, 1:28 PM CDTMesoscale DiscussionSPCCrawford, Franklin, Howard, Johnson, Little River, Logan and 5 more92 min
Apr 25, 3:08 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Baxter, Boone, Bradley, Calhoun and 29 more37 min
Apr 25, 3:22 PM CDTTornado Watch PDSSPCArkansas, Baxter, Boone, Bradley, Calhoun, Clark and 50 more8 hr
Apr 25, 4:34 PM CDTMesoscale DiscussionSPCArkansas, Clay, Craighead, Crittenden, Cross, Greene and 11 more56 min
Apr 25, 4:50 PM CDTTornado Watch PDSSPCClay, Craighead, Crittenden, Cross, Greene, Lee and 4 more7 hr
Apr 24, 7:35 PM CDTMesoscale DiscussionSPCBeaver2 hr
Apr 24, 11:58 PM CDTMesoscale DiscussionSPCAlfalfa, Beaver, Blaine, Canadian, Custer, Dewey and 14 more92 min
Apr 25, 5:24 PM CDTMesoscale DiscussionSPCBeckham, Caddo, Canadian, Cleveland, Comanche, Cotton and 13 more66 min
Apr 24, 8:48 PM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coleman, Collin, Comanche and 36 more117 min
Apr 24, 11:25 PM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Camp, Coke, Coleman and 39 more65 min
Apr 25, 3:29 AM CDTMesoscale DiscussionSPCBosque, Camp, Collin, Dallas, Delta, Denton and 24 more61 min
Apr 25, 2:16 PM CDTMesoscale DiscussionSPCAngelina, Bastrop, Bell, Blanco, Brazos, Burleson and 27 more59 min
Apr 25, 2:41 PM CDTTornado WatchSPCAnderson, Angelina, Bastrop, Bell, Blanco, Bosque and 49 more9 hr
Apr 25, 5:21 PM CDTMesoscale DiscussionSPCBosque, Delta, Ellis, Henderson, Hill, Hopkins and 7 more54 min
Apr 25, 6:57 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Bell, Blanco, Brazos, Burleson and 22 more2 hr

Nearby

Mesoscale Discussions in Texas, 2011Mesoscale Discussions in Oklahoma, 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.