Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 580

April 25, 20119 states

The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2011, 7:34 PM CDT for 9 states. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
Apr 25, 2011, 7:34 PM CDT (00:34 UTC)
Expired
Apr 25, 2011, 9:30 PM CDT
In force
116 min
Issued by
the Storm Prediction Center
All 118 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Clay 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, Grant County, AR, Greene County, AR, Hot Spring County, AR, Jackson County, AR, Jefferson County, AR, Lafayette County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Miller County, AR, Mississippi County, AR, Monroe County, AR, Nevada County, AR, Ouachita County, AR, Phillips County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, Union County, AR, White County, AR, Woodruff County, AR, Alexander County, IL, Franklin County, IL, Gallatin County, IL, Hardin County, IL, Jackson County, IL, Johnson County, IL, Massac County, IL, Pope County, IL, Pulaski County, IL, Saline County, IL, Union County, IL, White County, IL, Williamson County, IL, Posey County, IN, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Henderson County, KY, Hickman County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, Union County, KY, Webster County, KY, Bossier Parish, LA, Claiborne Parish, LA, Lincoln Parish, LA, Union Parish, LA, Webster Parish, LA, Bollinger County, MO, Cape Girardeau County, MO, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Perry County, MO, Scott County, MO, Stoddard County, MO, Benton County, MS, Bolivar County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Lafayette County, MS, Leflore County, MS, Marshall County, MS, Panola County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tunica County, MS, Washington County, MS, Yalobusha County, MS, Carroll County, TN, Chester County, TN, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Haywood County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Madison County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN, Camp County, TX, Cass County, TX, Marion County, TX, Morris County, TX

The radar

The Little Rock radar (KLZK), 77 km from the middle of the area, began a volume at 00:33 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

Little Rock, AR (KLZK), launched 00:00Z, 0.6 hours before the alert went out and 139 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, Little Rock, AR at 00:00Z on 2011-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1507 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, Little Rock, AR at 00:00Z on 2011-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 388 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
1507 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
914 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
388 m²/s²
0-3 km storm-relative helicity
511 m²/s²
Significant tornado parameter
4.0
Supercell composite
19.6

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 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 26, 6:43 PM CDTMesoscale DiscussionSPCColumbia, Lafayette, Little River, Miller, Union2 hr
Apr 26, 12:26 PM CDTMesoscale DiscussionSPCChampaign, Clark, Douglas, Edgar, Ford, Iroquois and 1 more94 min
Apr 26, 2:02 PM CDTTornado WatchSPCChampaign, Clark, Coles, Cumberland, Douglas, Edgar and 2 more7 hr
Apr 26, 4:38 PM CDTMesoscale DiscussionSPCClark, Crawford, Edwards, Gallatin, Hamilton, Jasper and 5 more37 min
Apr 26, 4:50 PM CDTTornado WatchSPCGallatin, Saline, Wabash, White5 hr
Apr 26, 3:53 PM CDTMesoscale DiscussionSPCCarroll, Cass, Elkhart, Fulton, Howard, Jasper and 13 more67 min
Apr 25, 11:42 PM CDTSevere Thunderstorm WatchSPCAllen, Barren, Breckinridge, Butler, Caldwell, Calloway and 19 more7 hr
Apr 26, 2:04 AM CDTMesoscale DiscussionSPCAllen, Barren, Breckinridge, Edmonson, Grayson, Hardin and 5 more56 min
Apr 26, 12:49 PM CDTMesoscale DiscussionSPCMartin56 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 Arkansas, 2011Mesoscale Discussions in Mississippi, 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.