Alert archive / Mississippi / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 300

May 13, 20114 states

The Storm Prediction Center issued this severe thunderstorm watch at May 13, 2011, 5:54 PM CDT for 4 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: May 13, 2011, 5:54 PM CDT (22:54 UTC)
Expired: May 13, 2011, 11:49 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 91 counties

Colbert County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Marion County, AL, Pickens County, AL, Sumter County, AL, Allen County, KY, Butler County, KY, Caldwell County, KY, Calloway County, KY, Christian County, KY, Crittenden County, KY, Daviess County, KY, Hancock County, KY, Henderson County, KY, Hopkins County, KY, Livingston County, KY, Logan County, KY, Lyon County, KY, Marshall County, KY, McLean County, KY, Muhlenberg County, KY, Ohio County, KY, Simpson County, KY, Todd County, KY, Trigg County, KY, Union County, KY, Warren County, KY, Webster County, KY, Alcorn County, MS, Attala County, MS, Benton County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Grenada County, MS, Holmes County, MS, Itawamba County, MS, Kemper County, MS, Lafayette County, MS, Lauderdale County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Lowndes County, MS, Monroe County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pontotoc County, MS, Prentiss County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Bedford County, TN, Benton County, TN, Cheatham County, TN, Davidson County, TN, Decatur County, TN, Dickson County, TN, Giles County, TN, Hardin County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lawrence County, TN, Lewis County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Perry County, TN, Robertson County, TN, Rutherford County, TN, Stewart County, TN, Sumner County, TN, Wayne County, TN, Williamson County, TN, Wilson County, TN

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: 40%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 40%
One or more hailstones of 2 inches or more: 10%
Six or more combined severe hail and wind reports: 80%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 13, 6:03 PM CDT	Flash Flood Warning	JAN	Montgomery, Webster	117 min
May 13, 6:05 PM CDT	Tornado Warning	MEG	Alcorn, Tishomingo	40 min
May 13, 6:06 PM CDT	Flash Flood Warning	MEG	Alcorn, Benton, Lafayette, Marshall, Pontotoc, Prentiss and 2 more	3 hr
May 13, 6:07 PM CDT	Severe Thunderstorm Warning	MEG	Lafayette, Lee, Pontotoc, Union	53 min
May 13, 6:17 PM CDT	Severe Thunderstorm Warning	MEG	Prentiss, Tippah, Tishomingo	58 min
May 13, 6:34 PM CDT	Tornado Warning	MEG	Tishomingo	41 min
May 13, 6:40 PM CDT	Severe Thunderstorm Warning	HUN	Colbert, Lauderdale	50 min
May 13, 6:43 PM CDT	Tornado Warning	MEG	Tishomingo	32 min
May 13, 6:45 PM CDT	Severe Thunderstorm Warning	JAN	Choctaw, Montgomery, Webster	41 min
May 13, 6:55 PM CDT	Tornado Warning	JAN	Choctaw, Webster	20 min
May 13, 7:16 PM CDT	Severe Thunderstorm Warning	JAN	Choctaw, Noxubee, Oktibbeha, Winston	44 min
May 13, 7:44 PM CDT	Flash Flood Warning	JAN	Choctaw, Clay, Oktibbeha, Webster	96 min
May 13, 8:01 PM CDT	Severe Thunderstorm Warning	JAN	Choctaw, Noxubee, Oktibbeha, Winston	44 min
May 13, 8:15 PM CDT	Severe Thunderstorm Warning	MEG	Itawamba, Lee, Monroe	35 min
May 13, 8:22 PM CDT	Tornado Warning	JAN	Noxubee, Winston	38 min
May 13, 8:35 PM CDT	Flash Flood Warning	JAN	Choctaw, Noxubee, Winston	115 min
May 13, 8:37 PM CDT	Severe Thunderstorm Warning	BMX	Lamar, Marion	20 min
May 13, 8:47 PM CDT	Severe Thunderstorm Warning	JAN	Noxubee	43 min
May 13, 8:53 PM CDT	Severe Thunderstorm Warning	JAN	Kemper, Neshoba, Noxubee, Winston	52 min
May 13, 9:28 PM CDT	Severe Thunderstorm Warning	BMX	Greene, Pickens, Sumter	39 min
May 13, 11:17 PM CDT	Severe Thunderstorm Warning	JAN	Clarke, Lauderdale	28 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

Nashville Metro, TN (KBNA), launched 12:00Z, 10.9 hours before the alert went out and 153 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: 1225 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 983 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 13, 11:22 AM CDT	Mesoscale Discussion	SPC	Cherokee, Etowah	113 min
May 13, 5:03 PM CDT	Mesoscale Discussion	SPC	Colbert, Cullman, Fayette, Franklin, Lamar, Lauderdale and 8 more	57 min
May 13, 12:31 PM CDT	Severe Thunderstorm Watch	SPC	Alexander, Hardin, Johnson, Massac, Pope, Pulaski and 1 more	6 hr
May 13, 4:40 PM CDT	Mesoscale Discussion	SPC	Bond, Brown, Calhoun, Cass, Christian, Clinton and 40 more	95 min
May 13, 12:01 PM CDT	Mesoscale Discussion	SPC	Carlisle, Fulton, Graves, Hickman	89 min
May 13, 2:44 PM CDT	Mesoscale Discussion	SPC	Ballard, Carlisle, Fulton, Graves, Hickman	2 hr
May 13, 2:47 PM CDT	Mesoscale Discussion	SPC	Harlan, Letcher	58 min
May 13, 12:10 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Blount, Bradley, Campbell, Carter, Claiborne and 24 more	6 hr

Nearby

Severe Thunderstorm Watches in Mississippi, 2011 Severe Thunderstorm Watches in Tennessee, 2011 Severe Thunderstorm Watches in Kentucky, 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.