Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 685

May 1, 20115 states

The Storm Prediction Center issued this mesoscale discussion at May 1, 2011, 5:43 PM CDT for 5 states. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
May 1, 2011, 5:43 PM CDT (22:43 UTC)
Expired
May 1, 2011, 7:15 PM CDT
In force
92 min
Issued by
the Storm Prediction Center
All 110 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Jackson County, AR, Jefferson County, AR, Lafayette County, AR, Lee County, AR, Lincoln County, AR, Little River County, AR, Lonoke County, AR, Miller County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Nevada County, AR, Ouachita County, AR, Phillips County, AR, Pike County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Sevier County, AR, St. Francis County, AR, Union County, AR, White County, AR, Woodruff County, AR, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Union Parish, LA, Webster Parish, LA, Alcorn County, MS, Benton County, MS, Bolivar County, MS, Coahoma County, MS, DeSoto County, MS, Lafayette County, MS, Marshall County, MS, Panola County, MS, Prentiss County, MS, Quitman County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Benton County, TN, Carroll County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Lauderdale County, TN, Madison County, TN, McNairy County, TN, Perry County, TN, Shelby County, TN, Tipton County, TN, Wayne County, TN, Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Franklin County, TX, Freestone County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Hopkins County, TX, Kaufman County, TX, Limestone County, TX, Marion County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Rains County, TX, Red River County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Little Rock radar (KLZK), 116 km from the middle of the area, began a volume at 22:46 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 nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 10.7 hours before the alert went out and 209 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 2011-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2344 joules per kilogram.LCLEL10008507005003002001001 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 2011-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 277 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
2344 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
499 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
277 m²/s²
0-3 km storm-relative helicity
370 m²/s²
Significant tornado parameter
4.9
Supercell composite
18.4

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 30, 7:49 PM CDTMesoscale DiscussionSPCClay, Greene, Izard, Lawrence, Randolph, Sharp and 1 more56 min
Apr 30, 8:47 PM CDTMesoscale DiscussionSPCArkansas, Clark, Conway, Faulkner, Garland, Grant and 12 more58 min
Apr 30, 9:26 PM CDTMesoscale DiscussionSPCHempstead, Howard, Little River, Miller, Sevier64 min
Apr 30, 11:39 PM CDTMesoscale DiscussionSPCArkansas, Clark, Cleburne, Conway, Craighead, Cross and 31 more66 min
May 1, 1:16 AM CDTMesoscale DiscussionSPCArkansas, Clark, Cleburne, Conway, Craighead, Crittenden and 37 more59 min
May 1, 3:50 AM CDTMesoscale DiscussionSPCLee, Monroe, Phillips2 hr
May 1, 8:30 AM CDTMesoscale DiscussionSPCClark, Dallas, Garland, Hempstead, Hot Spring, Howard and 9 more30 min
May 1, 8:45 AM CDTSevere Thunderstorm WatchSPCClark, Columbia, Dallas, Garland, Hempstead, Hot Spring and 10 more6 hr
May 1, 12:12 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 34 more93 min
May 1, 12:47 PM CDTTornado WatchSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 27 more8 hr
May 1, 3:18 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 37 more87 min
May 1, 5:42 PM CDTMesoscale DiscussionSPCClark, Dallas, Garland, Grant, Hempstead, Hot Spring and 14 more3 hr
May 1, 1:14 AM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coleman, Collin, Comanche and 28 more2 hr
May 1, 1:40 AM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Brown, Callahan, Clay, Coleman and 31 more7 hr
May 1, 3:19 AM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Collin, Comanche and 38 more86 min
May 1, 4:45 AM CDTTornado WatchSPCAnderson, Bowie, Camp, Cass, Cherokee, Delta and 21 more4 hr
May 1, 7:29 AM CDTMesoscale DiscussionSPCArcher, Baylor, Brown, Callahan, Clay, Coleman and 34 more91 min

Nearby

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Texas, 2011Mesoscale Discussions in Tennessee, 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.