Alert archive / Tennessee / Severe Thunderstorm Watches in 2006

Severe Thunderstorm Watch 366

May 20, 20065 states

The Storm Prediction Center issued this severe thunderstorm watch at May 20, 2006, 12:19 PM CDT for 5 states. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued: May 20, 2006, 12:19 PM CDT (17:19 UTC)
Expired: May 20, 2006, 8:00 PM CDT
In force: 8 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 60 kt

All 90 counties

DeKalb County, AL, Jackson County, AL, Limestone County, AL, Madison County, AL, Marshall County, AL, Banks County, GA, Catoosa County, GA, Dade County, GA, Dawson County, GA, Elbert County, GA, Fannin County, GA, Franklin County, GA, Gilmer County, GA, Gordon County, GA, Habersham County, GA, Hall County, GA, Hart County, GA, Lumpkin County, GA, Murray County, GA, Pickens County, GA, Rabun County, GA, Stephens County, GA, Towns County, GA, Union County, GA, Walker County, GA, White County, GA, Whitfield County, GA, Buncombe County, NC, Cabarrus County, NC, Cherokee County, NC, Clay County, NC, Cleveland County, NC, Gaston County, NC, Graham County, NC, Haywood County, NC, Henderson County, NC, Jackson County, NC, Lincoln County, NC, Macon County, NC, Mecklenburg County, NC, Polk County, NC, Rutherford County, NC, Swain County, NC, Transylvania County, NC, Union County, NC, Abbeville County, SC, Anderson County, SC, Cherokee County, SC, Chester County, SC, Greenville County, SC, Greenwood County, SC, Laurens County, SC, Oconee County, SC, Pickens County, SC, Spartanburg County, SC, Union County, SC, York County, SC, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Cannon County, TN, Coffee County, TN, Cumberland County, TN, DeKalb County, TN, Franklin County, TN, Grundy County, TN, Hamilton County, TN, Knox County, TN, Lincoln County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Moore County, TN, Morgan County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Rutherford County, TN, Sequatchie County, TN, Sevier County, TN, Smith County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Wilson County, TN

The radar

The Northeast Alabama radar (KHTX), 140 km from the middle of the area, began a volume at 17:20 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.

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: 50%
One or more gusts of 65 knots or more: 30%
Ten or more severe hail reports: 50%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 90%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 20, 12:32 PM CDT	Severe Thunderstorm Warning	OHX	Warren	43 min
May 20, 12:51 PM CDT	Severe Thunderstorm Warning	MRX	Bledsoe	24 min
May 20, 1:03 PM CDT	Severe Thunderstorm Warning	GSP	Stephens	15 min
May 20, 1:09 PM CDT	Severe Thunderstorm Warning	MRX	Sequatchie	21 min
May 20, 1:10 PM CDT	Severe Thunderstorm Warning	GSP	Anderson, Oconee	65 min
May 20, 1:16 PM CDT	Severe Thunderstorm Warning	MRX	Meigs, Rhea	29 min
May 20, 1:20 PM CDT	Severe Thunderstorm Warning	GSP	Pickens	44 min
May 20, 1:28 PM CDT	Severe Thunderstorm Warning	MRX	Hamilton	32 min
May 20, 1:32 PM CDT	Severe Thunderstorm Warning	GSP	Hart	14 min
May 20, 1:42 PM CDT	Severe Thunderstorm Warning	MRX	Meigs, Rhea	33 min
May 20, 1:45 PM CDT	Severe Thunderstorm Warning	GSP	Greenville	60 min
May 20, 1:53 PM CDT	Severe Thunderstorm Warning	MRX	Bradley, McMinn	22 min
May 20, 2:00 PM CDT	Severe Thunderstorm Warning	GSP	Laurens	60 min
May 20, 2:02 PM CDT	Severe Thunderstorm Warning	GSP	Cleveland	46 min
May 20, 2:04 PM CDT	Severe Thunderstorm Warning	FFC	Towns	26 min
May 20, 2:04 PM CDT	Severe Thunderstorm Warning	GSP	Rabun	56 min
May 20, 2:14 PM CDT	Tornado Warning	MRX	Bradley	16 min
May 20, 2:14 PM CDT	Tornado Warning	MRX	Bradley	31 min
May 20, 2:16 PM CDT	Severe Thunderstorm Warning	MRX	Blount, Knox	44 min
May 20, 2:20 PM CDT	Severe Thunderstorm Warning	GSP	Abbeville	33 min
May 20, 2:25 PM CDT	Tornado Warning	MRX	Polk	50 min
May 20, 2:30 PM CDT	Severe Thunderstorm Warning	GSP	Spartanburg	23 min
May 20, 2:34 PM CDT	Severe Thunderstorm Warning	GSP	Cherokee, York	56 min
May 20, 2:36 PM CDT	Severe Thunderstorm Warning	GSP	Union	36 min
May 20, 2:36 PM CDT	Severe Thunderstorm Warning	GSP	Oconee	54 min
May 20, 2:38 PM CDT	Severe Thunderstorm Warning	FFC	Fannin, Murray	37 min
May 20, 2:38 PM CDT	Severe Thunderstorm Warning	GSP	Greenwood	67 min
May 20, 2:57 PM CDT	Severe Thunderstorm Warning	MRX	Blount	48 min
May 20, 3:02 PM CDT	Severe Thunderstorm Warning	MRX	Knox, Sevier	43 min
May 20, 3:03 PM CDT	Severe Thunderstorm Warning	GSP	Anderson, Pickens	57 min
May 20, 3:08 PM CDT	Severe Thunderstorm Warning	GSP	Polk, Rutherford	38 min
May 20, 3:10 PM CDT	Severe Thunderstorm Warning	FFC	Fannin, Gilmer	35 min
May 20, 3:14 PM CDT	Severe Thunderstorm Warning	GSP	Swain	34 min
May 20, 3:17 PM CDT	Severe Thunderstorm Warning	MRX	Bradley, Polk	43 min
May 20, 3:20 PM CDT	Severe Thunderstorm Warning	FFC	Towns, Union	25 min
May 20, 3:28 PM CDT	Severe Thunderstorm Warning	GSP	York	62 min
May 20, 3:30 PM CDT	Severe Thunderstorm Warning	GSP	Cherokee	60 min
May 20, 3:31 PM CDT	Severe Thunderstorm Warning	GSP	Greenville	59 min
May 20, 3:37 PM CDT	Severe Thunderstorm Warning	GSP	Oconee	53 min
May 20, 3:40 PM CDT	Severe Thunderstorm Warning	FFC	Gilmer, Murray	35 min
May 20, 3:41 PM CDT	Severe Thunderstorm Warning	FFC	Fannin, Lumpkin, Union	34 min
May 20, 3:42 PM CDT	Severe Thunderstorm Warning	MRX	Cocke, Sevier	33 min
May 20, 3:44 PM CDT	Severe Thunderstorm Warning	GSP	Cleveland	61 min
May 20, 3:49 PM CDT	Severe Thunderstorm Warning	FFC	Towns	14 min
May 20, 3:52 PM CDT	Severe Thunderstorm Warning	GSP	Greenwood	53 min
May 20, 3:56 PM CDT	Severe Thunderstorm Warning	GSP	Spartanburg	52 min
May 20, 4:00 PM CDT	Severe Thunderstorm Warning	GSP	Anderson	60 min
May 20, 4:04 PM CDT	Severe Thunderstorm Warning	MRX	Blount	26 min
May 20, 4:07 PM CDT	Severe Thunderstorm Warning	GSP	Gaston	53 min
May 20, 4:11 PM CDT	Severe Thunderstorm Warning	FFC	Lumpkin	34 min
May 20, 4:11 PM CDT	Severe Thunderstorm Warning	MRX	Sevier	34 min
May 20, 4:14 PM CDT	Severe Thunderstorm Warning	FFC	Fannin, Gilmer	16 min
May 20, 4:15 PM CDT	Severe Thunderstorm Warning	GSP	Abbeville, Laurens	40 min
May 20, 4:17 PM CDT	Severe Thunderstorm Warning	GSP	York	73 min
May 20, 4:18 PM CDT	Severe Thunderstorm Warning	FFC	Dawson	12 min
May 20, 4:25 PM CDT	Severe Thunderstorm Warning	FFC	Hall, White	34 min
May 20, 4:26 PM CDT	Severe Thunderstorm Warning	GSP	Rutherford	44 min
May 20, 4:30 PM CDT	Severe Thunderstorm Warning	FFC	Dawson, Fannin, Gilmer	15 min
May 20, 4:40 PM CDT	Severe Thunderstorm Warning	GSP	Cleveland	45 min
May 20, 4:43 PM CDT	Severe Thunderstorm Warning	FFC	Lumpkin	31 min
May 20, 4:45 PM CDT	Severe Thunderstorm Warning	GSP	Mecklenburg	60 min
May 20, 4:45 PM CDT	Severe Thunderstorm Warning	GSP	Greenwood	41 min
May 20, 4:46 PM CDT	Severe Thunderstorm Warning	MRX	Bradley	29 min
May 20, 5:08 PM CDT	Severe Thunderstorm Warning	GSP	Gaston	49 min
May 20, 5:20 PM CDT	Severe Thunderstorm Warning	HUN	Franklin	35 min
May 20, 5:25 PM CDT	Severe Thunderstorm Warning	GSP	Jackson, Transylvania	34 min
May 20, 5:29 PM CDT	Severe Thunderstorm Warning	OHX	Grundy	21 min
May 20, 5:32 PM CDT	Severe Thunderstorm Warning	MRX	Marion, Sequatchie	28 min
May 20, 5:42 PM CDT	Severe Thunderstorm Warning	GSP	Pickens	41 min
May 20, 6:02 PM CDT	Severe Thunderstorm Warning	MRX	Hamilton	43 min
May 20, 6:13 PM CDT	Severe Thunderstorm Warning	FFC	Fannin, Murray	32 min
May 20, 6:24 PM CDT	Severe Thunderstorm Warning	MRX	Marion	24 min
May 20, 6:33 PM CDT	Severe Thunderstorm Warning	FFC	Catoosa, Whitfield	42 min
May 20, 6:38 PM CDT	Severe Thunderstorm Warning	GSP	Abbeville	31 min
May 20, 6:44 PM CDT	Severe Thunderstorm Warning	FFC	Union	46 min
May 20, 6:48 PM CDT	Severe Thunderstorm Warning	FFC	Gilmer	42 min
May 20, 7:01 PM CDT	Severe Thunderstorm Warning	FFC	Murray	44 min
May 20, 7:03 PM CDT	Severe Thunderstorm Warning	MRX	Cocke, Sevier	42 min
May 20, 7:20 PM CDT	Severe Thunderstorm Warning	MRX	Monroe	40 min
May 20, 7:21 PM CDT	Severe Thunderstorm Warning	FFC	Fannin, Lumpkin	39 min
May 20, 7:24 PM CDT	Severe Thunderstorm Warning	MRX	Meigs, Rhea	36 min
May 20, 7:30 PM CDT	Severe Thunderstorm Warning	FFC	Gilmer	49 min
May 20, 7:34 PM CDT	Severe Thunderstorm Warning	GSP	Rabun	20 min
May 20, 7:43 PM CDT	Severe Thunderstorm Warning	MRX	McMinn	32 min
May 20, 7:54 PM CDT	Severe Thunderstorm Warning	FFC	Dawson, Pickens	51 min
May 20, 7:58 PM CDT	Severe Thunderstorm Warning	MRX	Cherokee, Clay	47 min
May 20, 7:59 PM CDT	Severe Thunderstorm Warning	MRX	Monroe	46 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, 5.3 hours before the alert went out and 194 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: 191 J/kg
Mixed-layer CIN: -239 J/kg
Mixed-layer LCL: 1108 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 134 m²/s²
0-3 km storm-relative helicity: 169 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 20, 11:40 AM CDT	Mesoscale Discussion	SPC	DeKalb, Jackson, Limestone, Madison	2 hr
May 20, 5:45 PM CDT	Mesoscale Discussion	SPC	Jackson, Lauderdale, Limestone, Madison	90 min
May 20, 6:31 PM CDT	Mesoscale Discussion	SPC	Lauderdale, Limestone	29 min
May 20, 6:59 PM CDT	Severe Thunderstorm Watch	SPC	Lauderdale	6 hr
May 20, 2:57 AM CDT	Mesoscale Discussion	SPC	Rabun, Towns	63 min
May 20, 3:38 PM CDT	Mesoscale Discussion	SPC	Banks, Catoosa, Dade, Dawson, Elbert, Fannin and 15 more	97 min
May 20, 4:13 PM CDT	Severe Thunderstorm Watch	SPC	Barrow, Bartow, Burke, Chattooga, Cherokee, Clarke and 25 more	4 hr
May 19, 11:07 PM CDT	Mesoscale Discussion	SPC	Cherokee, Clay, Graham, Macon, Swain	23 min
May 19, 11:09 PM CDT	Severe Thunderstorm Watch	SPC	Cherokee, Clay, Graham, Haywood, Jackson, Macon and 2 more	6 hr
May 20, 2:04 PM CDT	Mesoscale Discussion	SPC	Anson, Cabarrus, Cleveland, Gaston, Hoke, Lincoln and 7 more	86 min
May 20, 2:34 PM CDT	Severe Thunderstorm Watch	SPC	Anson, Bladen, Brunswick, Columbus, New Hanover, Pender and 3 more	7 hr

Nearby

Severe Thunderstorm Watches in Tennessee, 2006 Severe Thunderstorm Watches in Georgia, 2006 Severe Thunderstorm Watches in North Carolina, 2006 Every severe thunderstorm watch in 2006

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.