Alert archive / Tennessee / Mesoscale Discussions in 2011

Mesoscale Discussion 411

April 11, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Apr 11, 2011, 10:41 AM CDT for 4 states. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued
Apr 11, 2011, 10:41 AM CDT (15:41 UTC)
Expired
Apr 11, 2011, 11:45 AM CDT
In force
64 min
Issued by
the Storm Prediction Center
All 105 counties

Colbert County, AL, Cullman County, AL, Fayette County, AL, Franklin County, AL, Jackson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Morgan County, AL, Pickens County, AL, Walker County, AL, Winston County, AL, Adair County, KY, Allen County, KY, Barren County, KY, Casey County, KY, Clinton County, KY, Cumberland County, KY, Green County, KY, McCreary County, KY, Metcalfe County, KY, Monroe County, KY, Pulaski County, KY, Russell County, KY, Taylor County, KY, Wayne 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, Coahoma County, MS, Grenada County, MS, Holmes County, MS, Humphreys County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Leflore County, MS, Lowndes County, MS, Marshall County, MS, Monroe County, MS, Montgomery County, MS, Noxubee County, MS, Oktibbeha County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Bedford County, TN, Bledsoe County, TN, Cannon County, TN, Cheatham County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hardin County, TN, Hickman County, TN, Jackson County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Moore County, TN, Overton County, TN, Perry County, TN, Pickett County, TN, Putnam County, TN, Rutherford County, TN, Scott County, TN, Sequatchie County, TN, Smith County, TN, Sumner County, TN, Trousdale County, TN, Van Buren County, TN, Warren County, TN, Wayne County, TN, White County, TN, Williamson County, TN, Wilson County, TN

The radar

The Northeast Alabama radar (KHTX), 140 km from the middle of the area, began a volume at 15:45 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

Nashville Metro, TN (KBNA), launched 12:00Z, 3.7 hours before the alert went out and 132 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, Nashville Metro, TN at 12:00Z on 2011-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 539 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, Nashville Metro, TN at 12:00Z on 2011-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 234 square meters per square second.1939587897Sfc1 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
539 J/kg
Mixed-layer CIN
-94 J/kg
Mixed-layer LCL
942 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
234 m²/s²
0-3 km storm-relative helicity
233 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.4

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 11, 8:58 AM CDTMesoscale DiscussionSPCColbert, Cullman, Fayette, Franklin, Lamar, Lauderdale and 7 more62 min
Apr 11, 3:56 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Calhoun, Chilton, Choctaw and 32 more34 min
Apr 11, 4:05 PM CDTTornado WatchSPCBibb, Blount, Chilton, Choctaw, Clarke, Dallas and 16 more6 hr
Apr 11, 5:11 PM CDTTornado WatchSPCColbert, Cullman, DeKalb, Franklin, Jackson, Lauderdale and 5 more7 hr
Apr 11, 5:53 PM CDTMesoscale DiscussionSPCBibb, Greene, Jefferson, Shelby, Tuscaloosa97 min
Apr 11, 6:42 PM CDTMesoscale DiscussionSPCAutauga, Bullock, Calhoun, Chambers, Cherokee, Chilton and 12 more33 min
Apr 11, 10:31 AM CDTTornado WatchSPCAdair, Allen, Anderson, Barren, Bourbon, Boyle and 26 more6 hr
Apr 11, 11:24 AM CDTMesoscale DiscussionSPCBoyd, Breathitt, Carter, Clay, Elliott, Estill and 19 more36 min
Apr 11, 11:47 AM CDTTornado WatchSPCBath, Bell, Boyd, Breathitt, Carter, Clay and 31 more6 hr
Apr 11, 12:37 PM CDTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bourbon, Boyle and 31 more53 min
Apr 11, 2:44 PM CDTMesoscale DiscussionSPCBath, Bell, Boyd, Breathitt, Carter, Clay and 31 more61 min
Apr 11, 9:46 AM CDTMesoscale DiscussionSPCAttala, Benton, Bolivar, Calhoun, Carroll, Chickasaw and 37 more29 min

Nearby

Mesoscale Discussions in Tennessee, 2011Mesoscale Discussions in Mississippi, 2011Mesoscale Discussions in Alabama, 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.