Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 434

April 15, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Apr 15, 2011, 1:27 AM CDT for 5 states. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Apr 15, 2011, 1:27 AM CDT (06:27 UTC)
Expired
Apr 15, 2011, 3:00 AM CDT
In force
93 min
Issued by
the Storm Prediction Center
All 60 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Cleburne 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, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Lawrence County, AR, Lee County, AR, Lincoln County, AR, Lonoke 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, Sharp County, AR, St. Francis County, AR, Union County, AR, White County, AR, Woodruff County, AR, Bienville Parish, LA, Bossier Parish, LA, Claiborne Parish, LA, East Carroll Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Dunklin County, MO, Pemiscot County, MO, Bolivar County, MS, Coahoma County, MS, DeSoto County, MS, Quitman County, MS, Tunica County, MS, Washington County, MS, Shelby County, TN, Tipton County, TN

The radar

The Little Rock radar (KLZK), 64 km from the middle of the area, began a volume at 06:29 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, 6.5 hours before the alert went out and 168 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 2011-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 195 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 2011-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 square meters per square second.1939587897Sfc1 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
195 J/kg
Mixed-layer CIN
-128 J/kg
Mixed-layer LCL
1615 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
170 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

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 14, 7:33 PM CDTMesoscale DiscussionSPCBoone, Calhoun, Carroll, Clark, Cleburne, Cleveland and 34 more117 min
Apr 14, 9:06 PM CDTTornado WatchSPCBaxter, Benton, Boone, Bradley, Calhoun, Carroll and 45 more6 hr
Apr 14, 11:11 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Clark, Cleburne and 35 more94 min
Apr 15, 2:19 AM CDTTornado WatchSPCArkansas, Ashley, Baxter, Bradley, Calhoun, Chicot and 38 more8 hr
Apr 15, 12:29 PM CDTMesoscale DiscussionSPCClay, Crittenden, Mississippi61 min
Apr 15, 2:09 PM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lee and 3 more7 hr
Apr 15, 3:32 PM CDTMesoscale DiscussionSPCClay, Greene58 min
Apr 15, 5:57 PM CDTMesoscale DiscussionSPCMississippi2 hr
Apr 14, 11:24 PM CDTSevere Thunderstorm WatchSPCBossier, Caddo, Claiborne, De Soto, Webster3 hr
Apr 14, 11:56 PM CDTMesoscale DiscussionSPCBossier, Caddo, De Soto, Webster94 min
Apr 15, 4:21 AM CDTMesoscale DiscussionSPCCaldwell, Catahoula, Concordia, East Carroll, Franklin, Grant and 6 more84 min
Apr 15, 7:32 AM CDTTornado WatchSPCAvoyelles, Caldwell, Catahoula, Concordia, East Carroll, Franklin and 8 more7 hr
Apr 15, 10:28 AM CDTMesoscale DiscussionSPCCaldwell, Catahoula, Concordia, East Carroll, Franklin, LaSalle and 4 more2 hr
Apr 15, 1:30 PM CDTMesoscale DiscussionSPCAvoyelles, Catahoula, Concordia, East Baton Rouge, East Feliciana, Pointe Coupee and 6 more2 hr
Apr 15, 2:41 PM CDTTornado WatchSPCAcadia, Ascension, Assumption, Avoyelles, Concordia, East Baton Rouge and 19 more7 hr
Apr 15, 3:35 PM CDTMesoscale DiscussionSPCAcadia, Ascension, Avoyelles, Concordia, East Baton Rouge, East Feliciana and 15 more85 min
Apr 15, 6:09 PM CDTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 12 more96 min
Apr 15, 11:21 AM CDTTornado WatchSPCGeorge, Greene, Perry, Stone, Wayne9 hr
Apr 15, 12:47 PM CDTTornado WatchSPCAudrain, Bollinger, Butler, Cape Girardeau, Carter, Crawford and 29 more9 hr

Nearby

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Louisiana, 2011Mesoscale Discussions in Mississippi, 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.