Alert archive / Tennessee / Mesoscale Discussions in 2011

Mesoscale Discussion 173

February 28, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Feb 28, 2011, 11:25 AM CST for 5 states. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued
Feb 28, 2011, 11:25 AM CST (17:25 UTC)
Expired
Feb 28, 2011, 1:00 PM CST
In force
95 min
Issued by
the Storm Prediction Center
All 102 counties

Blount County, AL, Colbert County, AL, Cullman County, AL, DeKalb 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, Marshall County, AL, Morgan County, AL, Walker County, AL, Winston County, AL, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Itawamba County, MS, Lee County, MS, Lowndes County, MS, Monroe County, MS, Montgomery County, MS, Oktibbeha County, MS, Pontotoc County, MS, Prentiss County, MS, Tishomingo County, MS, Webster County, MS, Graham County, NC, Swain County, NC, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Cannon County, TN, Carter County, TN, Claiborne County, TN, Clay County, TN, Cocke County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grainger County, TN, Greene County, TN, Grundy County, TN, Hamblen County, TN, Hamilton County, TN, Hancock County, TN, Hardin County, TN, Hawkins County, TN, Hickman County, TN, Jackson County, TN, Jefferson County, TN, Johnson County, TN, Knox County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Loudon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Perry County, TN, Pickett County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Rutherford County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Smith County, TN, Sullivan County, TN, Unicoi County, TN, Union County, TN, Van Buren County, TN, Warren County, TN, Washington County, TN, Wayne County, TN, White County, TN, Williamson County, TN, Wilson County, TN, City of Bristol, VA, Russell County, VA, Scott County, VA, Washington County, VA

The radar

The Northeast Alabama radar (KHTX), 38 km from the middle of the area, began a volume at 17:29 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, 5.4 hours before the alert went out and 121 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 2011-02-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 948 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 2011-02-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 369 square meters per square second.1939587897117136Sfc1 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
948 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
795 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
369 m²/s²
0-3 km storm-relative helicity
404 m²/s²
Significant tornado parameter
2.6
Supercell composite
9.4

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
Feb 28, 5:47 AM CSTMesoscale DiscussionSPCColbert, Franklin, Jackson, Lamar, Lauderdale, Lawrence and 5 more28 min
Feb 28, 5:59 AM CSTTornado WatchSPCColbert, Cullman, DeKalb, Fayette, Franklin, Jackson and 10 more7 hr
Feb 28, 12:19 PM CSTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bullock, Butler, Clarke and 15 more86 min
Feb 28, 12:29 PM CSTTornado WatchSPCAutauga, Barbour, Bibb, Blount, Bullock, Calhoun and 41 more7 hr
Feb 28, 3:36 PM CSTMesoscale DiscussionSPCAutauga, Bibb, Bullock, Calhoun, Chambers, Cherokee and 24 more84 min
Feb 28, 5:16 PM CSTMesoscale DiscussionSPCBaldwin, Barbour, Butler, Clarke, Coffee, Conecuh and 12 more89 min
Feb 28, 5:28 AM CSTMesoscale DiscussionSPCAlcorn, Attala, Benton, Bolivar, Calhoun, Carroll and 50 more62 min
Feb 28, 4:04 PM CSTSevere Thunderstorm WatchSPCAlamance, Anson, Chatham, Cumberland, Davidson, Durham and 25 more5 hr
Feb 28, 5:42 PM CSTMesoscale DiscussionSPCAnson, Chatham, Harnett, Hoke, Johnston, Lee and 6 more93 min
Feb 28, 1:05 AM CSTMesoscale DiscussionSPCBenton, Carroll, Chester, Crockett, Decatur, Dyer and 18 more25 min
Feb 28, 1:33 AM CSTTornado WatchSPCBenton, Carroll, Cheatham, Chester, Crockett, Dickson and 19 more7 hr
Feb 28, 4:47 AM CSTTornado WatchSPCBuchanan, Dickenson, Lee, Russell, Scott, Washington and 3 more5 hr
Feb 28, 7:36 AM CSTMesoscale DiscussionSPCAlbemarle, Alleghany, Amherst, Appomattox, Arlington, Augusta and 64 more24 min
Feb 28, 7:57 AM CSTTornado WatchSPCAlbemarle, Alleghany, Amherst, Appomattox, Arlington, Augusta and 67 more9 hr
Feb 28, 11:49 AM CSTMesoscale DiscussionSPCAppomattox, Bedford, Buckingham, Campbell, Caroline, Carroll and 20 more56 min

Nearby

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