Alert archive / Tennessee / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 48, NWS Morristown, TN

May 4, 20214 counties in Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at May 4, 2021, 8:37 AM CDT for 4 counties in Tennessee. It was in force for 38 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
May 4, 2021, 8:37 AM CDT (13:37 UTC)
Expired
May 4, 2021, 9:15 AM CDT
In force
38 min
Issued by
NWS Morristown, TN
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties Bledsoe County, TN, Morgan County, TN, Rhea County, TN, Roane County, TN

The radar

The Knoxville radar (KMRX), 126 km from the middle of the area, began a volume at 13:38 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
May 4, 8:45 AM CDTTSTM WND DMG2 Ene High Point, TNSEVERAL TREES DOWN ALONG HWY 62 IN THE CHESTNUT RIDGE COMMUNITY.

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
May 4, 5:13 AM CDTSevere Thunderstorm WatchSPC5 hr
May 4, 8:37 AM CDTSevere Thunderstorm WatchSPC3 hr

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 1.6 hours before the alert went out and 280 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 2021-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 590 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 2021-05-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 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
590 J/kg
Mixed-layer CIN
-114 J/kg
Mixed-layer LCL
753 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
213 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

452 
WUUS54 KMRX 041337
SVRMRX
TNC007-129-143-145-041415-
/O.NEW.KMRX.SV.W.0048.210504T1337Z-210504T1415Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Morristown TN
937 AM EDT Tue May 4 2021

The National Weather Service in Morristown has issued a

* Severe Thunderstorm Warning for...
  Southern Morgan County in east Tennessee...
  Northeastern Rhea County in east Tennessee...
  Northeastern Bledsoe County in east Tennessee...
  Roane County in east Tennessee...

* Until 1015 AM EDT/915 AM CDT/.

* At 937 AM EDT/837 AM CDT/, severe thunderstorms were located along
  a line extending from 11 miles west of Wartburg to near Fairfield
  Glade to 13 miles northeast of Spencer, moving east at 35 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Oak Ridge, Kingston, Rockwood, Wartburg, Fairview, Oliver Springs,
  Spring City, Midtown, Harriman and Oakdale.

This includes Interstate 40 in Tennessee between mile markers 341 and
358.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3577 8504 3575 8503 3576 8492 3586 8473
      3591 8468 3598 8471 3609 8480 3609 8483
      3611 8486 3617 8480 3608 8436 3605 8434
      3600 8432 3580 8445 3571 8468 3574 8472
      3570 8472 3570 8477 3565 8485 3576 8524
TIME...MOT...LOC 1337Z 287DEG 30KT 3610 8478 3593 8493 3582 8524 

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

BW
1 follow-up statement
123 
WWUS54 KMRX 041405
SVSMRX

Severe Weather Statement
National Weather Service Morristown TN
1005 AM EDT Tue May 4 2021

TNC129-041414-
/O.CAN.KMRX.SV.W.0048.000000T0000Z-210504T1415Z/
Morgan TN-
1005 AM EDT Tue May 4 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN MORGAN COUNTY IS
CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until noon EDT/1100 AM
CDT/ for east Tennessee. A Severe Thunderstorm Watch also remains in
effect until 200 PM EDT/100 PM CDT/ for east Tennessee.

LAT...LON 3576 8524 3577 8504 3575 8503 3576 8492
      3583 8477 3591 8468 3595 8458 3595 8455
      3596 8455 3598 8452 3599 8444 3605 8434
      3600 8432 3580 8445 3571 8467 3574 8472
      3570 8472 3570 8477 3565 8485
TIME...MOT...LOC 1404Z 287DEG 30KT 3604 8454 3587 8469 3576 8500 

$$

TNC007-143-145-041415-
/O.CON.KMRX.SV.W.0048.000000T0000Z-210504T1415Z/
Rhea TN-Bledsoe TN-Roane TN-
1005 AM EDT Tue May 4 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1015 AM
EDT/915 AM CDT/ FOR NORTHEASTERN RHEA...NORTHEASTERN BLEDSOE AND
ROANE COUNTIES...

At 1004 AM EDT/904 AM CDT/, severe thunderstorms were located along a
line extending from near Wartburg to Rockwood to 9 miles northwest of
Spring City, moving east at 35 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Oak Ridge, Kingston, Rockwood, Fairview, Oliver Springs, Spring City,
Midtown, Harriman, Stinging Fork Falls State Park and Eagle Furnace.

This includes Interstate 40 in Tennessee between mile markers 341 and
358.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3576 8524 3577 8504 3575 8503 3576 8492
      3583 8477 3591 8468 3595 8458 3595 8455
      3596 8455 3598 8452 3599 8444 3605 8434
      3600 8432 3580 8445 3571 8467 3574 8472
      3570 8472 3570 8477 3565 8485
TIME...MOT...LOC 1404Z 287DEG 30KT 3604 8454 3587 8469 3576 8500 

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

BW

The office that day

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

IssuedProductOfficeCountiesLasted
May 3, 7:29 PM CDTSpecial Weather StatementMRXGreene, Unicoi, Washington46 min
May 3, 7:47 PM CDTSpecial Weather StatementMRXHamblen, Jefferson43 min
May 4, 2:10 AM CDTSevere Thunderstorm WarningMRXMorgan, Roane50 min
May 4, 2:53 AM CDTSevere Thunderstorm WarningMRXAnderson, Morgan, Roane52 min
May 4, 2:56 AM CDTSpecial Weather StatementMRXMorgan49 min
May 4, 3:12 AM CDTSpecial Weather StatementMRXMorgan48 min
May 4, 3:40 AM CDTSevere Thunderstorm WarningMRXAnderson, Knox30 min
May 4, 3:45 AM CDTSpecial Weather StatementMRXBlount45 min
May 4, 3:57 AM CDTAreal Flood AdvisoryMRXAnderson, Morgan, Roane3 hr
May 4, 4:14 AM CDTSpecial Weather StatementMRXKnox46 min
May 4, 4:34 AM CDTSpecial Weather StatementMRXBlount41 min
May 4, 5:05 AM CDTSevere Thunderstorm WarningMRXBlount, Sevier30 min
May 4, 5:11 AM CDTAreal Flood AdvisoryMRXAnderson, Knox3 hr
May 4, 5:16 AM CDTAreal Flood AdvisoryMRXBlount3 hr
May 4, 5:52 AM CDTSpecial Weather StatementMRXSevier53 min
May 4, 6:00 AM CDTFlash Flood WarningMRXBlount, Sevier3 hr
May 4, 6:24 AM CDTAreal Flood AdvisoryMRXScott3 hr
May 4, 6:58 AM CDTSpecial Weather StatementMRXCocke47 min
May 4, 8:05 AM CDTSpecial Weather StatementMRXMorgan, Scott40 min
May 4, 8:18 AM CDTSpecial Weather StatementMRXHamilton27 min
May 4, 8:48 AM CDTSevere Thunderstorm WarningMRXBledsoe, Rhea27 min
May 4, 8:50 AM CDTSpecial Weather StatementMRXAnderson, Campbell, Claiborne, Union40 min
May 4, 8:53 AM CDTSpecial Weather StatementMRXHamilton, Marion, Sequatchie67 min
May 4, 9:03 AM CDTSevere Thunderstorm WarningMRXAnderson, Blount, Knox, Loudon, Roane13 min
May 4, 9:18 AM CDTSpecial Weather StatementMRXMcMinn, Meigs57 min
May 4, 9:24 AM CDTSpecial Weather StatementMRXBlount, Knox36 min
May 4, 9:37 AM CDTSpecial Weather StatementMRXHamblen38 min
May 4, 9:41 AM CDTSevere Thunderstorm WarningMRXBlount, Jefferson, Knox, Sevier34 min
May 4, 9:45 AM CDTSevere Thunderstorm WarningMRXBlount, Monroe30 min
May 4, 10:10 AM CDTSevere Thunderstorm WarningMRXCocke, Jefferson, Sevier22 min
May 4, 10:11 AM CDTFlash Flood WarningMRXHamilton, Marion, Sequatchie3 hr
May 4, 10:29 AM CDTAreal Flood WarningMRXBlount, Sevier6 hr
May 4, 10:44 AM CDTAreal Flood AdvisoryMRXBlount, Monroe2 hr
May 4, 10:47 AM CDTAreal Flood AdvisoryMRXBlount, Sevier118 min
May 4, 11:06 AM CDTSpecial Weather StatementMRXPolk24 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.