Alert archive / Tennessee / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 166, NWS Nashville, TN

December 11, 2021Coffee County, Grundy County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Dec 11, 2021, 7:22 AM CST for Coffee County, Grundy County, Tennessee. It was in force for 38 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Dec 11, 2021, 7:22 AM CST (13:22 UTC)
Expired
Dec 11, 2021, 8:00 AM CST
In force
38 min
Issued by
NWS Nashville, TN
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Coffee County, TN, Grundy County, TN

The radar

The Northeast Alabama radar (KHTX), 59 km from the middle of the area, began a volume at 13:23 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 was reported inside it

TimeReportWhereRemark
Dec 11, 7:36 AM CSTTORNADO1 N Coalmont, TNTHE TORNADO TOUCHED DOWN IN COALMONT AND QUICKLY PRODUCED 90 MPH WINDS THAT UPROOTED MANY TREES ON FREEMONT ROAD. IT MOVED NORTHEAST AND BLEW OUT THE WALLS OF A METAL BUILDING STRUCTURE AND DOWNED ADDITIONAL TREES ON 20TH AVENUE SOUTH NEAR HIGHWAY 108. THE TOR
Dec 11, 7:39 AM CSTTSTM WND DMG1 Ne Coalmont, TNTREES DOWN NEAR COALMONT IN GRUNDY COUNTY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Dec 11, 3:41 AM CSTTornado WatchSPC6 hr

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 1.4 hours before the alert went out and 248 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, Peachtre/Fal Fld, GA at 12:00Z on 2021-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 182 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Peachtre/Fal Fld, GA at 12:00Z on 2021-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 268 square meters per square second.1939587897Sfc1 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
182 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
625 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
268 m²/s²
0-3 km storm-relative helicity
271 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.8

Open this sounding in Storm Lab

The text

As transmitted.

704 
WUUS54 KOHX 111322
SVROHX
TNC031-061-111400-
/O.NEW.KOHX.SV.W.0166.211211T1322Z-211211T1400Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Nashville TN
722 AM CST Sat Dec 11 2021

The National Weather Service in Nashville has issued a

* Severe Thunderstorm Warning for...
  Southeastern Coffee County in Middle Tennessee...
  Grundy County in Middle Tennessee...

* Until 800 AM CST.

* At 722 AM CST, a severe thunderstorm was located 10 miles southeast
  of Manchester, moving east at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Gruetli-Laager, Tracy City, Monteagle, Altamont, Coalmont, Palmer,
  Beersheba Springs, Hillsboro, Pelham and Fiery Gizzard State Park.

This includes Interstate 24 between mile markers 121 and 135.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 AM CST for Middle
Tennessee.

For your protection move to an interior room on the lowest floor of a
building.

A Tornado Watch remains in effect until 1100 AM CST for Middle
Tennessee.

&&

LAT...LON 3522 8578 3524 8582 3522 8587 3529 8591
      3532 8599 3552 8596 3552 8587 3551 8582
      3553 8575 3553 8561 3549 8554 3543 8554
      3542 8551 3541 8551 3541 8549 3538 8549
      3532 8556 3529 8571 3524 8569 3522 8574
TIME...MOT...LOC 1322Z 268DEG 38KT 3539 8592 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

10
3 follow-up statements
140 
WWUS54 KOHX 111333
SVSOHX

Severe Weather Statement
National Weather Service Nashville TN
733 AM CST Sat Dec 11 2021

TNC031-111343-
/O.CAN.KOHX.SV.W.0166.000000T0000Z-211211T1400Z/
Coffee TN-
733 AM CST Sat Dec 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN COFFEE COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1100 AM CST for Middle
Tennessee.

LAT...LON 3524 8582 3522 8587 3529 8591 3533 8591
      3537 8587 3538 8589 3542 8589 3552 8588
      3551 8582 3553 8575 3553 8561 3549 8554
      3543 8554 3541 8549 3538 8549 3532 8556
      3529 8571 3524 8569 3522 8574 3522 8578
TIME...MOT...LOC 1333Z 268DEG 38KT 3539 8577 

$$

TNC061-111400-
/O.CON.KOHX.SV.W.0166.000000T0000Z-211211T1400Z/
Grundy TN-
733 AM CST Sat Dec 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 AM CST
FOR GRUNDY COUNTY...

At 733 AM CST, a severe thunderstorm was located 7 miles west of
Gruetli-Laager, or 17 miles east of Manchester, moving east at 45
mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Gruetli-Laager, Tracy City, Monteagle, Altamont, Coalmont, Palmer,
Beersheba Springs, Pelham and Fiery Gizzard State Park.

This includes Interstate 24 between mile markers 127 and 135.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 AM CST for Middle
Tennessee.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3524 8582 3522 8587 3529 8591 3533 8591
      3537 8587 3538 8589 3542 8589 3552 8588
      3551 8582 3553 8575 3553 8561 3549 8554
      3543 8554 3541 8549 3538 8549 3532 8556
      3529 8571 3524 8569 3522 8574 3522 8578
TIME...MOT...LOC 1333Z 268DEG 38KT 3539 8577 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

10
679 
WWUS54 KOHX 111345
SVSOHX

Severe Weather Statement
National Weather Service Nashville TN
745 AM CST Sat Dec 11 2021

TNC061-111400-
/O.CON.KOHX.SV.W.0166.000000T0000Z-211211T1400Z/
Grundy TN-
745 AM CST Sat Dec 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 AM CST
FOR NORTHEASTERN GRUNDY COUNTY...

At 745 AM CST, a severe thunderstorm was located over Gruetli-Laager,
or 12 miles west of Dunlap, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Gruetli-Laager, Altamont, Coalmont, Palmer and Beersheba Springs. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 AM CST for Middle
Tennessee.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3542 8574 3553 8569 3553 8561 3549 8554
      3543 8554 3541 8549 3538 8549 3532 8556
      3529 8568 3534 8573
TIME...MOT...LOC 1345Z 268DEG 38KT 3539 8561 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

10
235 
WWUS54 KOHX 111355
SVSOHX

Severe Weather Statement
National Weather Service Nashville TN
755 AM CST Sat Dec 11 2021

TNC061-111404-
/O.EXP.KOHX.SV.W.0166.000000T0000Z-211211T1400Z/
Grundy TN-
755 AM CST Sat Dec 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN GRUNDY COUNTY
WILL EXPIRE AT 800 AM CST...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 1100 AM CST for Middle
Tennessee.

LAT...LON 3542 8574 3553 8569 3553 8561 3549 8554
      3543 8554 3541 8549 3538 8549 3532 8556
      3529 8568 3534 8573
TIME...MOT...LOC 1354Z 268DEG 38KT 3539 8551 

$$

10

The office that day

Everything else NWS Nashville, TN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 10, 11:29 PM CSTTornado Warning Tornado observedOHXStewart46 min
Dec 11, 12:03 AM CSTTornado Warning Tornado observedConsiderable damage threatOHXMontgomery, Stewart16 min
Dec 11, 12:19 AM CSTSevere Thunderstorm WarningOHXMontgomery, Stewart41 min
Dec 11, 1:28 AM CSTSevere Thunderstorm WarningOHXStewart21 min
Dec 11, 1:47 AM CSTSevere Thunderstorm Warning Considerable damage threatOHXDickson, Hickman, Houston, Humphreys, Lewis, Montgomery and 2 more73 min
Dec 11, 2:03 AM CSTTornado WarningOHXHouston, Humphreys, Stewart27 min
Dec 11, 2:07 AM CSTTornado WarningOHXDickson, Hickman, Humphreys, Perry38 min
Dec 11, 2:23 AM CSTTornado WarningOHXDickson, Houston, Montgomery, Stewart37 min
Dec 11, 2:38 AM CSTTornado WarningOHXDickson, Hickman, Humphreys37 min
Dec 11, 2:39 AM CSTTornado WarningOHXCheatham, Dickson, Montgomery14 min
Dec 11, 2:47 AM CSTSevere Thunderstorm WarningOHXCheatham, Davidson, Dickson, Hickman, Lewis, Maury and 5 more58 min
Dec 11, 2:58 AM CSTTornado WarningOHXCheatham, Davidson, Dickson, Williamson32 min
Dec 11, 2:59 AM CSTTornado WarningOHXDavidson, Williamson31 min
Dec 11, 3:19 AM CSTSevere Thunderstorm WarningOHXDavidson, Hickman, Lewis, Marshall, Maury, Robertson and 5 more41 min
Dec 11, 3:21 AM CSTTornado WarningOHXDavidson, Sumner, Wilson39 min
Dec 11, 3:29 AM CSTSevere Thunderstorm Warning Destructive damage threatOHXDavidson, Rutherford, Smith, Sumner, Trousdale, Williamson and 1 more46 min
Dec 11, 3:33 AM CSTTornado WarningOHXDavidson, Macon, Smith, Sumner, Trousdale, Wilson42 min
Dec 11, 3:46 AM CSTTornado WarningOHXClay, Macon, Sumner, Trousdale44 min
Dec 11, 3:48 AM CSTSevere Thunderstorm WarningOHXLewis, Perry, Wayne42 min
Dec 11, 3:50 AM CSTSevere Thunderstorm Warning Considerable damage threatOHXClay, DeKalb, Jackson, Macon, Putnam, Smith and 3 more17 min
Dec 11, 3:56 AM CSTTornado WarningOHXLewis, Perry, Wayne13 min
Dec 11, 4:07 AM CSTTornado WarningOHXClay, Jackson, Macon, Overton, Smith, Trousdale38 min
Dec 11, 4:11 AM CSTSevere Thunderstorm Warning Considerable damage threatOHXClay, Fentress, Jackson, Macon, Overton, Pickett and 4 more34 min
Dec 11, 4:33 AM CSTTornado WarningOHXClay, Fentress, Overton, Pickett42 min
Dec 11, 5:01 AM CSTSevere Thunderstorm WarningOHXGiles, Lawrence, Lewis, Marshall, Maury29 min
Dec 11, 5:21 AM CSTSevere Thunderstorm WarningOHXOverton, Putnam27 min
Dec 11, 5:39 AM CSTSevere Thunderstorm WarningOHXGiles, Lawrence, Wayne36 min
Dec 11, 5:56 AM CSTSevere Thunderstorm WarningOHXGiles, Lawrence, Marshall, Maury34 min
Dec 11, 6:13 AM CSTTornado WarningOHXGiles15 min
Dec 11, 6:58 AM CSTSevere Thunderstorm WarningOHXBedford, Coffee, Grundy, Warren32 min
Dec 11, 7:35 AM CSTTornado WarningOHXGrundy25 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2021Every severe thunderstorm warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.