Alert archive / Tennessee / Tornado Watches in 2016

Tornado Watch 509

November 29, 20165 counties in Georgia; 8 counties in Tennessee

The Storm Prediction Center issued this tornado watch at Nov 29, 2016, 11:11 PM EST for 5 counties in Georgia; 8 counties in Tennessee. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Nov 29, 2016, 11:11 PM EST (04:11 UTC)
Expired
Nov 30, 2016, 3:55 AM EST
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt

Counties Catoosa County, GA, Chattooga County, GA, Dade County, GA, Walker County, GA, Whitfield County, GA, Bledsoe County, TN, Bradley County, TN, Hamilton County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Rhea County, TN, Sequatchie County, TN

The radar

The Northeast Alabama radar (KHTX), 59 km from the middle of the area, began a volume at 04:13 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
30%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Nov 29, 11:14 PM ESTTornado Warning Tornado observedMRXMarion31 min
Nov 29, 11:41 PM ESTSevere Thunderstorm WarningMRXBledsoe, Sequatchie23 min
Nov 29, 11:42 PM ESTSevere Thunderstorm WarningMRXMarion, Sequatchie48 min
Nov 29, 11:58 PM ESTTornado WarningMRXBledsoe, Hamilton, Marion, Sequatchie47 min
Nov 30, 12:05 AM ESTSevere Thunderstorm WarningFFCDade40 min
Nov 30, 12:09 AM ESTSevere Thunderstorm WarningMRXHamilton, Marion36 min
Nov 30, 12:23 AM ESTTornado WarningMRXBledsoe, Rhea24 min
Nov 30, 12:26 AM ESTSevere Thunderstorm WarningMRXMarion, Sequatchie34 min
Nov 30, 12:34 AM ESTTornado WarningMRXBradley, Hamilton26 min
Nov 30, 12:54 AM ESTTornado WarningMRXBradley, Hamilton, McMinn, Meigs36 min
Nov 30, 1:14 AM ESTSevere Thunderstorm WarningFFCDade, Walker31 min
Nov 30, 1:18 AM ESTTornado WarningFFCDade, Walker26 min
Nov 30, 1:20 AM ESTTornado WarningMRXMcMinn, Monroe25 min
Nov 30, 1:36 AM ESTSevere Thunderstorm WarningMRXMcMinn, Meigs24 min
Nov 30, 1:37 AM ESTSevere Thunderstorm WarningFFCCatoosa, Walker23 min
Nov 30, 1:41 AM ESTSevere Thunderstorm WarningMRXHamilton34 min
Nov 30, 1:53 AM ESTTornado WarningFFCCatoosa18 min
Nov 30, 2:00 AM ESTTornado WarningMRXBradley, Hamilton, Polk30 min
Nov 30, 2:07 AM ESTSevere Thunderstorm WarningMRXLoudon, McMinn, Monroe23 min
Nov 30, 2:29 AM ESTTornado WarningMRXBradley, McMinn, Monroe, Polk31 min
Nov 30, 3:13 AM ESTSevere Thunderstorm WarningMRXMarion, Sequatchie32 min
Nov 30, 3:41 AM ESTSevere Thunderstorm WarningMRXBledsoe, Hamilton, Marion, Meigs, Rhea, Sequatchie34 min
Nov 30, 3:47 AM ESTSevere Thunderstorm WarningFFCCatoosa, Dade, Walker43 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, 4.2 hours before the alert went out and 160 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 2016-11-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2016-11-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 321 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1648 m above ground
0-6 km bulk shear
90 kt
0-1 km storm-relative helicity
321 m²/s²
0-3 km storm-relative helicity
354 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

689 
WWUS20 KWNS 300407
SEL9  
SPC WW 300407
GAZ000-TNZ000-300900-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 509
NWS STORM PREDICTION CENTER NORMAN OK
1110 PM EST TUE NOV 29 2016

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  NORTHWEST GEORGIA
  SOUTHEAST TENNESSEE

* EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 1110 PM
  UNTIL 400 AM EST.

* PRIMARY THREATS INCLUDE...
  A COUPLE INTENSE TORNADOES POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
  ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE

SUMMARY...A CLUSTER OF SUPERCELL THUNDERSTORMS OVER NORTHEAST AL AND
SOUTHERN MIDDLE TN WILL TRACK NORTHEASTWARD AND AFFECT THE WATCH
AREA OVERNIGHT.  DAMAGING WIND GUSTS AND ISOLATED TORNADOES ARE THE
MAIN THREAT.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 30 STATUTE MILES
EAST AND WEST OF A LINE FROM 35 MILES SOUTH SOUTHWEST OF CHATTANOOGA
TN TO 50 MILES NORTH OF CHATTANOOGA TN. FOR A COMPLETE DEPICTION OF
THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS
WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 505...WW 507...WW 508...

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN
STORM MOTION VECTOR 24035.

...HART

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 29, 10:28 PM ESTMesoscale DiscussionSPCDade62 min
Nov 30, 12:17 AM ESTMesoscale DiscussionSPCCatoosa, Dade, Walker, Whitfield118 min
Nov 30, 2:07 AM ESTMesoscale DiscussionSPCCatoosa, Dade, Walker, Whitfield53 min
Nov 30, 3:54 AM ESTTornado WatchSPCBartow, Catoosa, Chattooga, Cherokee, Dade, Fannin and 10 more7 hr
Nov 30, 6:10 AM ESTMesoscale DiscussionSPCBartow, Carroll, Catoosa, Chattooga, Cherokee, Dade and 16 more95 min
Nov 30, 10:00 AM ESTMesoscale DiscussionSPCBartow, Carroll, Chattooga, Cherokee, Clayton, Cobb and 21 more2 hr
Nov 30, 12:06 PM ESTTornado WatchSPCBaker, Banks, Barrow, Bartow, Butts, Calhoun and 53 more6 hr
Nov 30, 1:59 PM ESTMesoscale DiscussionSPCBaker, Barrow, Butts, Calhoun, Chattahoochee, Clay and 41 more2 hr
Nov 30, 2:55 PM ESTMesoscale DiscussionSPCBaker, Baldwin, Banks, Barrow, Bibb, Bleckley and 70 more2 hr
Nov 30, 3:23 PM ESTSevere Thunderstorm WatchSPCBaldwin, Bibb, Bleckley, Columbia, Crisp, Dooly and 22 more3 hr
Nov 30, 5:43 PM ESTMesoscale DiscussionSPCColumbia, Elbert, Glascock, Hancock, Lincoln, McDuffie and 5 more92 min
Nov 30, 5:45 PM ESTMesoscale DiscussionSPCBaker, Calhoun, Decatur, Dougherty, Early, Grady and 7 more30 min
Nov 29, 7:43 PM ESTMesoscale DiscussionSPCHardin, Lawrence, Wayne92 min
Nov 29, 7:47 PM ESTTornado WatchSPCBedford, Coffee, Franklin, Giles, Grundy, Lewis and 5 more8 hr
Nov 29, 11:28 PM ESTTornado WatchSPCFranklin, Lincoln, Moore5 hr
Nov 30, 12:46 AM ESTMesoscale DiscussionSPCAnderson, Blount, Campbell, Claiborne, Grainger, Hamblen and 6 more119 min

Nearby

Tornado Watches in Tennessee, 2016Tornado Watches in Georgia, 2016Every tornado watch in 2016

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.