Alert archive / Tennessee / Mesoscale Discussions in 2011

Mesoscale Discussion 625

April 27, 2011Cherokee County, Clay County, Graham County, North Carolina; 16 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2011, 2:03 PM EDT for Cherokee County, Clay County, Graham County, North Carolina; 16 counties in Tennessee. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued: Apr 27, 2011, 2:03 PM EDT (18:03 UTC)
Expired: Apr 27, 2011, 3:00 PM EDT
In force: 57 min
Issued by: the Storm Prediction Center

Counties Cherokee County, NC, Clay County, NC, Graham County, NC, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Grundy County, TN, Hamilton County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Polk County, TN, Rhea County, TN, Roane County, TN, Sequatchie County, TN, Van Buren County, TN, Warren County, TN

The radar

The Northeast Alabama radar (KHTX), 123 km from the middle of the area, began a volume at 18:03 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.

Tornado Watch 238Apr 27, 4:35 PM EDT

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 6.1 hours before the alert went out and 163 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 714 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: -84 m²/s²
0-3 km storm-relative helicity: -38 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 27, 8:34 AM EDT	Tornado Watch	SPC	Cherokee, Clay	4 hr
Apr 27, 11:27 AM EDT	Tornado Watch	SPC	Cherokee, Clay	6 hr
Apr 27, 12:39 PM EDT	Mesoscale Discussion	SPC	Cherokee	66 min
Apr 27, 12:51 PM EDT	Mesoscale Discussion	SPC	Alamance, Anson, Bertie, Bladen, Cabarrus, Caswell and 47 more	84 min
Apr 27, 1:23 PM EDT	Tornado Watch	SPC	Alamance, Anson, Caswell, Chatham, Cumberland, Davidson and 28 more	5 hr
Apr 27, 3:22 PM EDT	Mesoscale Discussion	SPC	Alleghany, Ashe, Avery, Buncombe, Caldwell, Haywood and 6 more	83 min
Apr 27, 4:36 PM EDT	Tornado Watch PDS	SPC	Cherokee, Clay	8 hr
Apr 27, 6:00 PM EDT	Mesoscale Discussion	SPC	Alamance, Caswell, Durham, Franklin, Granville, Guilford and 5 more	60 min
Apr 27, 6:15 PM EDT	Tornado Watch	SPC	Alamance, Alleghany, Ashe, Caswell, Davidson, Durham and 15 more	6 hr
Apr 27, 6:41 PM EDT	Mesoscale Discussion	SPC	Alexander, Avery, Buncombe, Burke, Caldwell, Catawba and 16 more	34 min
Apr 27, 6:52 PM EDT	Tornado Watch PDS	SPC	Alexander, Avery, Buncombe, Burke, Caldwell, Catawba and 19 more	9 hr
Apr 27, 7:55 PM EDT	Mesoscale Discussion	SPC	Alamance, Caswell, Granville, Orange, Person, Rockingham	65 min
Apr 26, 8:59 PM EDT	Mesoscale Discussion	SPC	Bedford, Cheatham, Davidson, Dickson, Giles, Hardin and 11 more	2 hr
Apr 26, 10:13 PM EDT	Mesoscale Discussion	SPC	Benton, Carroll, Chester, Crockett, Dyer, Fayette and 16 more	62 min
Apr 26, 10:58 PM EDT	Tornado Watch	SPC	Bedford, Benton, Cannon, Carroll, Cheatham, Chester and 40 more	7 hr
Apr 27, 3:26 AM EDT	Tornado Watch	SPC	Franklin, Lincoln, Moore	6 hr
Apr 27, 5:33 AM EDT	Mesoscale Discussion	SPC	Bedford, Cannon, Clay, Coffee, Cumberland, DeKalb and 15 more	57 min
Apr 27, 6:07 AM EDT	Tornado Watch	SPC	Bedford, Bledsoe, Cannon, Clay, Coffee, Cumberland and 27 more	5 hr
Apr 27, 7:25 AM EDT	Mesoscale Discussion	SPC	Fayette, Hardeman, Shelby, Tipton	65 min
Apr 27, 9:08 AM EDT	Tornado Watch	SPC	Franklin, Lincoln, Moore	6 hr
Apr 27, 12:02 PM EDT	Tornado Watch PDS	SPC	Hardin, McNairy	8 hr
Apr 27, 1:08 PM EDT	Mesoscale Discussion	SPC	Benton, Carroll, Cheatham, Chester, Crockett, Decatur and 21 more	67 min
Apr 27, 1:42 PM EDT	Severe Thunderstorm Watch	SPC	Benton, Carroll, Cheatham, Chester, Crockett, Davidson and 27 more	5 hr
Apr 27, 2:05 PM EDT	Mesoscale Discussion	SPC	Franklin, Giles, Lawrence, Lincoln, Marshall, Maury and 1 more	85 min
Apr 27, 2:42 PM EDT	Tornado Watch PDS	SPC	Franklin, Lincoln, Moore	8 hr
Apr 27, 3:56 PM EDT	Mesoscale Discussion	SPC	Franklin, Lincoln, Marion	2 hr
Apr 27, 4:06 PM EDT	Mesoscale Discussion	SPC	Benton, Carroll, Cheatham, Chester, Crockett, Davidson and 22 more	54 min
Apr 27, 4:29 PM EDT	Tornado Watch	SPC	Carroll, Chester, Crockett, Decatur, Dyer, Fayette and 13 more	5 hr
Apr 27, 6:38 PM EDT	Mesoscale Discussion	SPC	Anderson, Bedford, Bledsoe, Blount, Bradley, Cannon and 36 more	97 min

Nearby

Mesoscale Discussions in Tennessee, 2011 Mesoscale Discussions in North Carolina, 2011 Every 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.