Alert archive / Tennessee / Tornado Watches in 2007

Tornado Watch 117

April 3, 200711 counties in Alabama; 9 counties in Georgia; 57 counties in Tennessee

The Storm Prediction Center issued this tornado watch at Apr 3, 2007, 8:03 PM CDT for 11 counties in Alabama; 9 counties in Georgia; 57 counties in Tennessee. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 3, 2007, 8:03 PM CDT (01:03 UTC)
Expired
Apr 4, 2007, 1:06 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 77 counties

Colbert County, AL, Cullman County, AL, DeKalb County, AL, Franklin County, AL, Jackson County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marshall County, AL, Morgan County, AL, Catoosa County, GA, Dade County, GA, Fannin County, GA, Gilmer County, GA, Murray County, GA, Towns County, GA, Union County, GA, Walker County, GA, Whitfield County, GA, Anderson County, TN, Bedford County, TN, Benton County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Campbell County, TN, Cannon County, TN, Cheatham County, TN, Clay County, TN, Coffee County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Dickson County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grundy County, TN, Hamilton County, TN, Hickman County, TN, Humphreys County, TN, Jackson County, TN, Knox County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Loudon County, TN, Macon 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, Robertson 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 Nashville radar (KOHX), 77 km from the middle of the area, began a volume at 01:04 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
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
95%
One or more gusts of 65 knots or more
20%
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
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 3, 8:06 PM CDTSevere Thunderstorm WarningOHXCheatham, Robertson39 min
Apr 3, 8:09 PM CDTSevere Thunderstorm WarningMRXCampbell, Scott51 min
Apr 3, 8:26 PM CDTSevere Thunderstorm WarningOHXDickson34 min
Apr 3, 8:28 PM CDTSevere Thunderstorm WarningOHXCumberland, White32 min
Apr 3, 8:32 PM CDTSevere Thunderstorm WarningOHXPerry28 min
Apr 3, 8:41 PM CDTSevere Thunderstorm WarningOHXHickman49 min
Apr 3, 8:57 PM CDTSevere Thunderstorm WarningMRXCampbell, Scott48 min
Apr 3, 8:57 PM CDTSevere Thunderstorm WarningOHXDavidson, Williamson, Wilson48 min
Apr 3, 9:00 PM CDTSevere Thunderstorm WarningOHXCumberland45 min
Apr 3, 9:07 PM CDTSevere Thunderstorm WarningOHXMaury23 min
Apr 3, 9:11 PM CDTSevere Thunderstorm WarningMRXAnderson, Claiborne, Union49 min
Apr 3, 9:12 PM CDTTornado WarningOHXCumberland33 min
Apr 3, 9:34 PM CDTSevere Thunderstorm WarningMRXRhea, Roane56 min
Apr 3, 9:34 PM CDTSevere Thunderstorm WarningOHXMarshall, Maury26 min
Apr 3, 9:38 PM CDTSevere Thunderstorm WarningOHXCannon, Rutherford37 min
Apr 3, 9:40 PM CDTSevere Thunderstorm WarningMRXGrainger, Hancock, Knox40 min
Apr 3, 9:44 PM CDTSevere Thunderstorm WarningOHXCumberland31 min
Apr 3, 9:48 PM CDTSevere Thunderstorm WarningHUNLauderdale42 min
Apr 3, 9:55 PM CDTSevere Thunderstorm WarningOHXBedford, Coffee35 min
Apr 3, 10:05 PM CDTSevere Thunderstorm WarningHUNLincoln, Moore40 min
Apr 3, 10:21 PM CDTSevere Thunderstorm WarningHUNFranklin39 min
Apr 3, 10:25 PM CDTSevere Thunderstorm WarningMRXMeigs35 min
Apr 3, 10:25 PM CDTSevere Thunderstorm WarningMRXBlount, Carter, Johnson, Loudon, Sevier, Sullivan and 2 more65 min
Apr 3, 10:28 PM CDTFlash Flood WarningMRXRoane2 hr
Apr 3, 10:32 PM CDTSevere Thunderstorm WarningMRXBledsoe, Marion, Rhea, Sequatchie43 min
Apr 3, 10:34 PM CDTTornado WarningHUNMadison26 min
Apr 3, 10:42 PM CDTSevere Thunderstorm WarningHUNColbert, Franklin, Lawrence48 min
Apr 3, 10:43 PM CDTSevere Thunderstorm WarningHUNLincoln20 min
Apr 3, 10:49 PM CDTSevere Thunderstorm WarningMRXHamilton56 min
Apr 3, 10:56 PM CDTSevere Thunderstorm WarningHUNLimestone21 min
Apr 3, 10:58 PM CDTSevere Thunderstorm WarningHUNJackson, Madison47 min
Apr 3, 11:00 PM CDTSevere Thunderstorm WarningHUNFranklin19 min
Apr 3, 11:08 PM CDTSevere Thunderstorm WarningFFCCatoosa, Dade, Walker, Whitfield52 min
Apr 3, 11:14 PM CDTTornado WarningHUNJackson24 min
Apr 3, 11:16 PM CDTSevere Thunderstorm WarningFFCFannin29 min
Apr 3, 11:21 PM CDTSevere Thunderstorm WarningMRXMarion24 min
Apr 3, 11:29 PM CDTSevere Thunderstorm WarningHUNFranklin, Lawrence31 min
Apr 3, 11:35 PM CDTSevere Thunderstorm WarningFFCUnion40 min
Apr 3, 11:38 PM CDTSevere Thunderstorm WarningHUNCullman37 min
Apr 3, 11:43 PM CDTSevere Thunderstorm WarningHUNDeKalb32 min
Apr 3, 11:46 PM CDTSevere Thunderstorm WarningHUNMarshall30 min
Apr 3, 11:58 PM CDTSevere Thunderstorm WarningFFCWalker32 min
Apr 4, 12:02 AM CDTSevere Thunderstorm WarningFFCFannin43 min
Apr 4, 12:16 AM CDTSevere Thunderstorm WarningHUNCullman14 min
Apr 4, 12:31 AM CDTSevere Thunderstorm WarningFFCUnion22 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 00:00Z, 1.1 hours before the alert went out and 64 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 00:00Z on 2007-04-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1678 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2007-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 200 square meters per square second.193958Sfc1 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
1678 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
1714 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
200 m²/s²
0-3 km storm-relative helicity
261 m²/s²
Significant tornado parameter
0.5
Supercell composite
10.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 3, 9:53 PM CDTSevere Thunderstorm WatchSPCBlount, Calhoun, Cherokee, Clay, Cleburne, Etowah and 12 more5 hr
Apr 3, 10:49 PM CDTMesoscale DiscussionSPCCullman, DeKalb, Jackson, Lawrence, Madison, Marshall and 1 more56 min
Apr 4, 2:07 AM CDTMesoscale DiscussionSPCAutauga, Bibb, Chambers, Chilton, Clay, Cleburne and 15 more113 min
Apr 3, 8:43 PM CDTSevere Thunderstorm WatchSPCRabun5 hr
Apr 3, 11:21 PM CDTSevere Thunderstorm WatchSPCBanks, Barrow, Bartow, Carroll, Chattooga, Cherokee and 27 more3 hr
Apr 3, 9:14 PM CDTMesoscale DiscussionSPCFayette, Hardeman61 min

Nearby

Tornado Watches in Tennessee, 2007Tornado Watches in Alabama, 2007Tornado Watches in Georgia, 2007Every tornado watch in 2007

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.