Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 599

April 26, 201125 counties in Arkansas; 6 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2011, 5:00 PM CDT for 25 counties in Arkansas; 6 counties in Oklahoma. It was in force for 30 min.

The area

The outline as issued.

The facts

Issued
Apr 26, 2011, 5:00 PM CDT (22:00 UTC)
Expired
Apr 26, 2011, 5:30 PM CDT
In force
30 min
Issued by
the Storm Prediction Center
All 31 counties

Baxter County, AR, Boone County, AR, Cleburne County, AR, Conway County, AR, Crawford County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Izard County, AR, Johnson County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Newton County, AR, Perry County, AR, Polk County, AR, Pope County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Stone County, AR, Van Buren County, AR, Washington County, AR, White County, AR, Yell County, AR, Haskell County, OK, Latimer County, OK, LeFlore County, OK, McIntosh County, OK, Pushmataha County, OK, Sequoyah County, OK

The radar

The Western Arkansas radar (KSRX), 46 km from the middle of the area, began a volume at 22:02 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 12:00Z, 10.0 hours before the alert went out and 186 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 12:00Z on 2011-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 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 12:00Z on 2011-04-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
8 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
466 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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, 7:34 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 33 more116 min
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, 5:08 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, 3:15 PM CDTMesoscale DiscussionSPCBeckham, Caddo, Canadian, Cleveland, Comanche, Cotton and 15 more90 min
Apr 26, 3:43 PM CDTSevere Thunderstorm WatchSPCAtoka, Beckham, Bryan, Caddo, Carter, Coal and 20 more6 hr

Nearby

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Oklahoma, 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.