Alert archive / Mississippi / Mesoscale Discussions in 2015

Mesoscale Discussion 271

April 10, 20156 counties in Alabama; 18 counties in Mississippi; 6 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Apr 10, 2015, 12:53 AM CDT for 6 counties in Alabama; 18 counties in Mississippi; 6 counties in Tennessee. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 10, 2015, 12:53 AM CDT (05:53 UTC)
Expired: Apr 10, 2015, 3:00 AM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 30 counties

Colbert County, AL, Franklin County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Marion County, AL, Alcorn County, MS, Benton County, MS, Calhoun County, MS, Chickasaw County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Marshall County, MS, Monroe County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Yalobusha County, MS, Giles County, TN, Hardin County, TN, Lawrence County, TN, Lewis County, TN, McNairy County, TN, Wayne County, TN

The radar

The Columbus AFB radar (KGWX), 89 km from the middle of the area, began a volume at 05:57 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 nearest sounding before it

Little Rock, AR (KBYH), launched 00:00Z, 5.9 hours before the alert went out and 117 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: 928 J/kg
Mixed-layer CIN: -88 J/kg
Mixed-layer LCL: 873 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 156 m²/s²
0-3 km storm-relative helicity: 232 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 7.1

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.

Issued	Product	Office	Counties	Lasted
Apr 10, 12:05 PM CDT	Mesoscale Discussion	SPC	Autauga, Baldwin, Barbour, Bullock, Butler, Choctaw and 19 more	85 min
Apr 10, 3:38 PM CDT	Mesoscale Discussion	SPC	Autauga, Baldwin, Barbour, Bullock, Butler, Chambers and 22 more	97 min
Apr 9, 10:01 PM CDT	Mesoscale Discussion	SPC	Alcorn, Benton, Bolivar, Calhoun, Chickasaw, Coahoma and 17 more	119 min
Apr 10, 1:54 AM CDT	Mesoscale Discussion	SPC	Bedford, Bledsoe, Cannon, Cheatham, Clay, Coffee and 33 more	96 min
Apr 10, 3:09 AM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bledsoe, Campbell, Cannon, Claiborne, Clay and 15 more	5 hr
Apr 10, 5:16 AM CDT	Mesoscale Discussion	SPC	Anderson, Blount, Campbell, Claiborne, Grainger, Greene and 10 more	59 min

Nearby

Mesoscale Discussions in Mississippi, 2015 Mesoscale Discussions in Alabama, 2015 Mesoscale Discussions in Tennessee, 2015 Every mesoscale discussion in 2015

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.