Alert archive / Arkansas / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 571

June 28, 20114 states

The Storm Prediction Center issued this severe thunderstorm watch at Jun 28, 2011, 11:51 AM CDT for 4 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Jun 28, 2011, 11:51 AM CDT (16:51 UTC)
Expired: Jun 28, 2011, 7:00 PM CDT
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2.5 in
Strongest gust expected: 60 kt

All 48 counties

Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Dallas County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Jefferson County, AR, Johnson County, AR, Lafayette County, AR, Lincoln County, AR, Little River County, AR, Logan County, AR, Miller County, AR, Montgomery County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Pope County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Sevier County, AR, Union County, AR, Yell County, AR, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, Lincoln Parish, LA, Union Parish, LA, Webster Parish, LA, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Franklin County, TX, Morris County, TX, Red River County, TX, Titus County, TX

The radar

The Little Rock radar (KLZK), 99 km from the middle of the area, began a volume at 16:52 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 20%
One or more EF2 to EF5 tornadoes: 5%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 50%
Six or more combined severe hail and wind reports: 80%

Warnings issued inside it

10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jun 28, 11:56 AM CDT	Severe Thunderstorm Warning	LZK	Clark, Hot Spring	34 min
Jun 28, 11:56 AM CDT	Severe Thunderstorm Warning	LZK	Clark, Hot Spring, Montgomery, Pike	49 min
Jun 28, 12:12 PM CDT	Severe Thunderstorm Warning	LZK	Garland, Perry, Yell	33 min
Jun 28, 12:29 PM CDT	Severe Thunderstorm Warning	LZK	Garland, Hot Spring, Perry, Saline	31 min
Jun 28, 3:37 PM CDT	Severe Thunderstorm Warning	SHV	McCurtain	53 min
Jun 28, 4:24 PM CDT	Severe Thunderstorm Warning	SHV	Sevier	51 min
Jun 28, 4:45 PM CDT	Tornado Warning	SHV	McCurtain	45 min
Jun 28, 5:14 PM CDT	Severe Thunderstorm Warning	SHV	McCurtain	61 min
Jun 28, 6:10 PM CDT	Severe Thunderstorm Warning	SHV	Bowie, Cass, Morris, Red River, Titus	65 min
Jun 28, 6:38 PM CDT	Severe Thunderstorm Warning	SHV	Franklin, Red River, Titus	52 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 4.9 hours before the alert went out and 206 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1494 J/kg
Mixed-layer CIN: -233 J/kg
Mixed-layer LCL: 869 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -47 m²/s²
0-3 km storm-relative helicity: -2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 27, 7:05 PM CDT	Mesoscale Discussion	SPC	Baxter, Benton, Boone, Carroll, Clay, Fulton and 9 more	115 min
Jun 28, 4:08 AM CDT	Mesoscale Discussion	SPC	Baxter, Benton, Boone, Carroll, Clay, Cleburne and 25 more	82 min
Jun 28, 4:17 AM CDT	Severe Thunderstorm Watch	SPC	Baxter, Boone, Carroll, Clay, Cleburne, Craighead and 20 more	8 hr
Jun 28, 6:34 AM CDT	Mesoscale Discussion	SPC	Arkansas, Clay, Cleburne, Conway, Craighead, Crittenden and 28 more	86 min
Jun 28, 7:06 AM CDT	Severe Thunderstorm Watch	SPC	Arkansas, Bradley, Calhoun, Clark, Cleveland, Conway and 22 more	5 hr
Jun 28, 9:52 AM CDT	Mesoscale Discussion	SPC	Ashley, Bradley, Calhoun, Chicot, Dallas, Drew and 1 more	113 min
Jun 28, 10:26 AM CDT	Severe Thunderstorm Watch	SPC	Ashley, Chicot	8 hr
Jun 28, 11:42 AM CDT	Mesoscale Discussion	SPC	Bradley, Calhoun, Clark, Columbia, Dallas, Garland and 13 more	93 min
Jun 28, 3:09 PM CDT	Mesoscale Discussion	SPC	Ashley, Bradley, Calhoun, Clark, Cleveland, Columbia and 27 more	96 min
Jun 28, 6:09 PM CDT	Mesoscale Discussion	SPC	Columbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more	96 min
Jun 28, 3:19 PM CDT	Mesoscale Discussion	SPC	Concordia, Tensas	116 min
Jun 28, 3:29 PM CDT	Mesoscale Discussion	SPC	Cimarron	91 min
Jun 28, 3:53 PM CDT	Severe Thunderstorm Watch	SPC	Atoka, Bryan, Carter, Choctaw, Coal, Johnston and 8 more	7 hr

Nearby

Severe Thunderstorm Watches in Arkansas, 2011 Severe Thunderstorm Watches in Texas, 2011 Severe Thunderstorm Watches in Louisiana, 2011 Every severe thunderstorm watch 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.