Alert archive / Tennessee / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 21, NWS Morristown, TN

February 12, 20209 counties in Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at Feb 12, 2020, 7:56 PM CST for 9 counties in Tennessee. It was in force for 64 min. 1 report 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: Feb 12, 2020, 7:56 PM CST (01:56 UTC)
Expired: Feb 12, 2020, 9:00 PM CST
In force: 64 min
Issued by: NWS Morristown, TN
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Bledsoe County, TN, Bradley County, TN, Hamilton County, TN, Loudon County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Rhea County, TN, Roane County, TN

The radar

The Northeast Alabama radar (KHTX), 114 km from the middle of the area, began a volume at 01:59 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

Time	Report	Where	Remark
Feb 12, 8:15 PM CST	TSTM WND DMG	Signal Mountain, TN	TREES BLOWN DOWN.

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 1.9 hours before the alert went out and 174 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: 548 m above ground
0-6 km bulk shear: 99 kt
0-1 km storm-relative helicity: 775 m²/s²
0-3 km storm-relative helicity: 947 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

189 
WUUS54 KMRX 130156
SVRMRX
TNC007-011-065-105-107-121-123-143-145-130300-
/O.NEW.KMRX.SV.W.0021.200213T0156Z-200213T0300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Morristown TN
856 PM EST Wed Feb 12 2020

The National Weather Service in Morristown has issued a

* Severe Thunderstorm Warning for...
  Rhea County in east Tennessee...
  Southwestern Loudon County in east Tennessee...
  Bradley County in east Tennessee...
  Eastern Bledsoe County in east Tennessee...
  Meigs County in east Tennessee...
  McMinn County in east Tennessee...
  Northwestern Monroe County in east Tennessee...
  Hamilton County in east Tennessee...
  Southwestern Roane County in east Tennessee...

* Until 1000 PM EST/900 PM CST/.

* At 855 PM EST/755 PM CST/, severe thunderstorms were located along
  a line extending from 7 miles northwest of Spring City to 7 miles
  north of Soddy-Daisy to near Trenton, moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Chattanooga, Cleveland, Athens, Dayton, Sweetwater, Decatur,
  Soddy-Daisy, Signal Mountain, Rossville and Etowah.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Prepare immediately for damaging winds. People outside should move 
immediately to shelter inside a strong building. Stay away from 
windows.

&&

LAT...LON 3498 8540 3526 8530 3535 8523 3537 8525
      3577 8504 3575 8503 3577 8490 3569 8431
      3527 8459 3527 8467 3524 8471 3523 8470
      3517 8470 3499 8478
TIME...MOT...LOC 0155Z 265DEG 36KT 3577 8495 3537 8518 3493 8547 

HAIL...<.75IN
WIND...60MPH
 
$$

DH

2 follow-up statements

699 
WWUS54 KMRX 130231
SVSMRX

Severe Weather Statement
National Weather Service Morristown TN
931 PM EST Wed Feb 12 2020

TNC007-130241-
/O.CAN.KMRX.SV.W.0021.000000T0000Z-200213T0300Z/
Bledsoe TN-
931 PM EST Wed Feb 12 2020

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN BLEDSOE COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

LAT...LON 3499 8531 3575 8473 3569 8431 3527 8459
      3527 8467 3524 8471 3523 8470 3517 8470
      3499 8478
TIME...MOT...LOC 0231Z 265DEG 36KT 3580 8453 3540 8476 3496 8505 

$$

TNC011-065-105-107-121-123-143-145-130300-
/O.CON.KMRX.SV.W.0021.000000T0000Z-200213T0300Z/
Rhea TN-Loudon TN-Bradley TN-Meigs TN-McMinn TN-Monroe TN-
Hamilton TN-Roane TN-
931 PM EST Wed Feb 12 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1000 PM EST
FOR SOUTHEASTERN RHEA...SOUTHWESTERN LOUDON...BRADLEY...MEIGS...
MCMINN...NORTHWESTERN MONROE...SOUTHEASTERN HAMILTON AND SOUTHWESTERN
ROANE COUNTIES...

At 931 PM EST, severe thunderstorms were located along a line
extending from near Fairview to 7 miles north of Charleston to near
Ringgold, moving east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Chattanooga, Cleveland, Athens, Sweetwater, Decatur, Etowah,
Lakesite, Charleston, Ridgeside and South Cleveland.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3499 8531 3575 8473 3569 8431 3527 8459
      3527 8467 3524 8471 3523 8470 3517 8470
      3499 8478
TIME...MOT...LOC 0231Z 265DEG 36KT 3580 8453 3540 8476 3496 8505 

HAIL...<.75IN
WIND...60MPH
 
$$

Diegan

710 
WWUS54 KMRX 130256
SVSMRX

Severe Weather Statement
National Weather Service Morristown TN
956 PM EST Wed Feb 12 2020

TNC011-065-105-107-121-123-143-145-130306-
/O.EXP.KMRX.SV.W.0021.000000T0000Z-200213T0300Z/
Rhea TN-Loudon TN-Bradley TN-Meigs TN-McMinn TN-Monroe TN-
Hamilton TN-Roane TN-
956 PM EST Wed Feb 12 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN RHEA...
SOUTHWESTERN LOUDON...BRADLEY...MEIGS...MCMINN...NORTHWESTERN
MONROE...SOUTHEASTERN HAMILTON AND SOUTHWESTERN ROANE COUNTIES WILL
EXPIRE AT 1000 PM EST...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with these thunderstorms.

LAT...LON 3499 8531 3575 8473 3569 8431 3527 8459
      3527 8467 3524 8471 3523 8470 3517 8470
      3499 8478
TIME...MOT...LOC 0256Z 265DEG 36KT 3582 8424 3542 8447 3498 8476 

$$

Diegan

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 12, 7:00 PM CST	Severe Thunderstorm Warning	MRX	Marion	45 min
Feb 12, 7:12 PM CST	Severe Thunderstorm Warning	MRX	Bledsoe, Hamilton, Rhea, Sequatchie	48 min
Feb 12, 7:17 PM CST	Special Weather Statement	MRX	Anderson, Campbell, Morgan, Scott	58 min
Feb 12, 7:22 PM CST	Severe Thunderstorm Warning	MRX	Campbell, Morgan, Scott	53 min
Feb 12, 7:30 PM CST	Severe Thunderstorm Warning	MRX	Hamilton, Marion, Sequatchie	45 min
Feb 12, 7:38 PM CST	Severe Thunderstorm Warning	MRX	Anderson, Campbell, Loudon, Morgan, Rhea, Roane and 1 more	52 min
Feb 12, 8:12 PM CST	Severe Thunderstorm Warning	MRX	Campbell, Claiborne, Grainger, Hancock, Scott, Union	48 min
Feb 12, 8:22 PM CST	Severe Thunderstorm Warning	MRX	Anderson, Blount, Campbell, Grainger, Jefferson, Knox and 3 more	53 min
Feb 12, 8:54 PM CST	Special Weather Statement	MRX	Grainger, Greene, Hamblen, Hancock, Hawkins	66 min
Feb 12, 8:59 PM CST	Special Weather Statement	MRX	Blount, Cocke, Jefferson, Monroe, Sevier	61 min
Feb 12, 9:42 PM CST	Special Weather Statement	MRX	Carter, Greene, Sullivan, Unicoi, Washington	48 min
Feb 13, 6:27 AM CST	River Flood Warning	MRX	Cocke	33 hr
Feb 13, 8:48 AM CST	River Flood Warning	MRX	Cocke, Jefferson	14 hr

Nearby

Severe Thunderstorm Warnings in Tennessee, 2020 Every severe thunderstorm warning in 2020

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.