Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 543

April 23, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2011, 8:09 PM CDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 23, 2011, 8:09 PM CDT (01:09 UTC)
Expired
Apr 23, 2011, 10:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 56 counties

Baxter County, AR, Boone County, AR, Clay County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Crawford County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Greene County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Johnson County, AR, Lawrence County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Newton County, AR, Perry County, AR, Polk County, AR, Pope County, AR, Randolph County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Sharp County, AR, Stone County, AR, Van Buren County, AR, Yell County, AR, Alexander County, IL, Johnson County, IL, Pulaski County, IL, Union County, IL, Williamson County, IL, Ballard County, KY, Carlisle County, KY, Fulton County, KY, Hickman County, KY, Bollinger County, MO, Butler County, MO, Cape Girardeau County, MO, Carter County, MO, Dunklin County, MO, Howell County, MO, Mississippi County, MO, New Madrid County, MO, Oregon County, MO, Pemiscot County, MO, Ripley County, MO, Scott County, MO, Stoddard County, MO, Wayne County, MO, Lake County, TN, Obion County, TN

The radar

The Little Rock radar (KLZK), 104 km from the middle of the area, began a volume at 01:12 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, 1.2 hours before the alert went out and 189 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 2011-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2011-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 135 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
747 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
135 m²/s²
0-3 km storm-relative helicity
283 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.0

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 23, 8:19 PM CDTTornado WatchSPCBaxter, Clay, Craighead, Fulton, Greene, Independence and 9 more4 hr
Apr 23, 10:40 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Clay, Fulton and 8 more95 min
Apr 24, 11:58 AM CDTMesoscale DiscussionSPCBaxter, Clay, Cleburne, Conway, Craighead, Faulkner and 19 more62 min
Apr 24, 12:27 PM CDTTornado WatchSPCBaxter, Clay, Cleburne, Conway, Craighead, Fulton and 16 more7 hr
Apr 24, 3:31 PM CDTMesoscale DiscussionSPCCleburne, Craighead, Greene, Independence, Izard, Jackson and 9 more59 min
Apr 24, 5:34 PM CDTMesoscale DiscussionSPCCrawford, Franklin, Madison, Polk, Scott, Sebastian and 1 more26 min
Apr 24, 5:36 PM CDTTornado WatchSPCConway, Crawford, Franklin, Garland, Johnson, Logan and 8 more7 hr
Apr 24, 6:23 PM CDTMesoscale DiscussionSPCBaxter, Clay, Cleburne, Conway, Craighead, Faulkner and 32 more2 hr
Apr 24, 3:01 PM CDTMesoscale DiscussionSPCAlexander, Hardin, Massac, Pope, Pulaski89 min

Nearby

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Illinois, 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.