Alert archive / Arkansas / Mesoscale Discussions in 2014

Mesoscale Discussion 439

April 27, 201451 counties in Arkansas; Butler County, Dunklin County, Pemiscot County, Missouri; 4 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2014, 8:43 PM CDT for 51 counties in Arkansas; Butler County, Dunklin County, Pemiscot County, Missouri; 4 counties in Oklahoma. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
Apr 27, 2014, 8:43 PM CDT (01:43 UTC)
Expired
Apr 27, 2014, 9:45 PM CDT
In force
62 min
Issued by
the Storm Prediction Center
All 58 counties

Clark County, AR, Clay County, AR, Cleburne County, AR, Cleveland County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Faulkner County, AR, Franklin County, AR, Garland County, AR, Grant County, AR, Greene County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Johnson County, AR, Lawrence County, AR, Lee County, AR, Little River County, AR, Logan County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Nevada County, AR, Perry County, AR, Pike County, AR, Poinsett County, AR, Polk County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Randolph County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Sevier County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Butler County, MO, Dunklin County, MO, Pemiscot County, MO, Choctaw County, OK, LeFlore County, OK, McCurtain County, OK, Pushmataha County, OK

The radar

The Little Rock radar (KLZK), 51 km from the middle of the area, began a volume at 01:45 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

Springfield, MO (KSGF), launched 00:00Z, 1.7 hours before the alert went out and 220 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, Springfield, MO at 00:00Z on 2014-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 409 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, Springfield, MO at 00:00Z on 2014-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 353 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
409 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
501 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
353 m²/s²
0-3 km storm-relative helicity
357 m²/s²
Significant tornado parameter
0.8
Supercell composite
6.8

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 27, 7:15 PM CDTMesoscale DiscussionSPCFaulkner30 min
Apr 27, 7:29 PM CDTMesoscale DiscussionSPCClay, Craighead, Crittenden, Cross, Greene, Mississippi and 1 more91 min
Apr 27, 7:53 PM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 4 more6 hr
Apr 27, 8:09 PM CDTMesoscale DiscussionSPCColumbia, Lafayette, Miller, Union66 min
Apr 27, 9:59 PM CDTMesoscale DiscussionSPCCalhoun, Clark, Cleburne, Cleveland, Columbia, Conway and 36 more91 min
Apr 27, 10:33 PM CDTTornado WatchSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Conway and 27 more7 hr
Apr 27, 11:08 PM CDTTornado WatchSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more6 hr
Apr 27, 11:21 PM CDTMesoscale DiscussionSPCArkansas, Baxter, Boone, Bradley, Calhoun, Carroll and 38 more84 min
Apr 27, 11:41 PM CDTMesoscale DiscussionSPCClay, Craighead, Crittenden, Cross, Greene, Mississippi and 2 more94 min
Apr 28, 1:43 AM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 6 more8 hr
Apr 28, 2:50 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 25 more115 min
Apr 28, 4:21 AM CDTMesoscale DiscussionSPCAshley, Bradley, Chicot, Columbia, Drew, Union54 min
Apr 28, 4:40 AM CDTTornado WatchSPCAshley, Chicot, Union7 hr
Apr 28, 7:16 AM CDTMesoscale DiscussionSPCChicot89 min
Apr 28, 9:53 AM CDTMesoscale DiscussionSPCChicot97 min
Apr 27, 8:40 PM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Carroll and 35 more65 min
Apr 28, 1:43 AM CDTMesoscale DiscussionSPCCape Girardeau, Franklin, Gasconade, Iron, Jefferson, Madison and 7 more92 min
Apr 28, 12:54 PM CDTMesoscale DiscussionSPCAudrain, Callaway, Clark, Crawford, Franklin, Gasconade and 19 more2 hr
Apr 28, 1:11 PM CDTTornado WatchSPCAudrain, Callaway, Clark, Crawford, Franklin, Gasconade and 16 more7 hr
Apr 28, 3:13 PM CDTMesoscale DiscussionSPCBollinger, Cape Girardeau, Mississippi, New Madrid, Perry, Scott and 1 more2 hr
Apr 28, 3:38 PM CDTMesoscale DiscussionSPCClark, Jefferson, Lincoln, Pike, Saint Charles, Saint Louis and 1 more2 hr

Nearby

Mesoscale Discussions in Arkansas, 2014Mesoscale Discussions in Oklahoma, 2014Mesoscale Discussions in Missouri, 2014Every mesoscale discussion in 2014

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.