Alert archive / Tennessee / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 86, NWS Morristown, TN

June 28, 20214 counties in Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at Jun 28, 2021, 6:57 PM EDT for 4 counties in Tennessee. It was in force for 48 min. 3 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
Jun 28, 2021, 6:57 PM EDT (22:57 UTC)
Expired
Jun 28, 2021, 7:45 PM EDT
In force
48 min
Issued by
NWS Morristown, TN
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Anderson County, TN, Campbell County, TN, Knox County, TN, Union County, TN

The radar

The Knoxville radar (KMRX), 53 km from the middle of the area, began a volume at 23:01 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
Jun 28, 7:20 PM EDTTSTM WND DMG2 Wnw Paulette, TNA FEW TREES DOWN.
Jun 28, 7:25 PM EDTTSTM WND DMG2 Nne Clinton, TNSEVERAL TREES DOWN NEAR THE MUSEUM OF APPALACHIA.
Jun 28, 7:30 PM EDTTSTM WND DMG3 Sw Norris, TNSEVERAL TREES DOWN ACROSS THE AREA.

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 12:00Z, 11.0 hours before the alert went out and 235 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 12:00Z on 2021-06-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 78 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, Nashville Metro, TN at 12:00Z on 2021-06-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -38 square meters per square second.1939Sfc1 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
78 J/kg
Mixed-layer CIN
-85 J/kg
Mixed-layer LCL
1282 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-38 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

524 
WUUS54 KMRX 282257
SVRMRX
TNC001-013-093-173-282345-
/O.NEW.KMRX.SV.W.0086.210628T2257Z-210628T2345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Morristown TN
657 PM EDT Mon Jun 28 2021

The National Weather Service in Morristown has issued a

* Severe Thunderstorm Warning for...
  North central Knox County in east Tennessee...
  Central Anderson County in east Tennessee...
  South central Campbell County in east Tennessee...
  Southwestern Union County in east Tennessee...

* Until 745 PM EDT.

* At 657 PM EDT, a severe thunderstorm was located near Plainview, or
  7 miles southwest of Maynardville, moving west at 15 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Clinton, Plainview, Halls, Rocky Top, Norris, Norris Dam State
  Park, Disney, Andersonville, Maloneyville and Paulette.

This includes Interstate 75 in Tennessee between mile markers 114 and
133.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3619 8380 3606 8384 3609 8430 3630 8420
TIME...MOT...LOC 2257Z 102DEG 7KT 3615 8387 

HAIL...0.75IN
WIND...60MPH
 
$$

DH
1 follow-up statement
549 
WWUS54 KMRX 282317
SVSMRX

Severe Weather Statement
National Weather Service Morristown TN
717 PM EDT Mon Jun 28 2021

TNC001-013-093-173-282345-
/O.CON.KMRX.SV.W.0086.000000T0000Z-210628T2345Z/
Knox TN-Anderson TN-Campbell TN-Union TN-
717 PM EDT Mon Jun 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM EDT
FOR NORTH CENTRAL KNOX...CENTRAL ANDERSON...SOUTH CENTRAL CAMPBELL
AND SOUTHWESTERN UNION COUNTIES...

At 716 PM EDT, a severe thunderstorm was located 9 miles northeast of
Clinton, moving west at 15 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Clinton, Halls, Rocky Top, Norris, Norris Dam State Park, Disney,
Andersonville and Paulette.

This includes Interstate 75 in Tennessee between mile markers 114 and
133.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3621 8388 3606 8391 3609 8430 3630 8420
TIME...MOT...LOC 2316Z 100DEG 14KT 3617 8398 

HAIL...0.75IN
WIND...60MPH
 
$$

DH

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 28, 3:33 PM EDTSpecial Weather StatementMRXCocke42 min
Jun 28, 4:11 PM EDTSpecial Weather StatementMRXMonroe49 min
Jun 28, 4:21 PM EDTSevere Thunderstorm WarningMRXMcMinn, Monroe39 min
Jun 28, 4:57 PM EDTSpecial Weather StatementMRXMonroe63 min
Jun 28, 5:19 PM EDTSpecial Weather StatementMRXRoane41 min
Jun 28, 6:06 PM EDTSpecial Weather StatementMRXKnox39 min
Jun 28, 6:11 PM EDTSevere Thunderstorm WarningMRXClaiborne, Grainger, Union49 min
Jun 28, 6:34 PM EDTSevere Thunderstorm WarningMRXUnion41 min
Jun 28, 6:53 PM EDTSpecial Weather StatementMRXClaiborne52 min
Jun 28, 7:14 PM EDTSpecial Weather StatementMRXCampbell46 min
Jun 28, 7:44 PM EDTSpecial Weather StatementMRXAnderson, Campbell61 min
Jun 28, 7:53 PM EDTSevere Thunderstorm WarningMRXCampbell, Scott52 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.