Severe Thunderstorm Warning 112, NWS Morristown, TN

018 
WWUS54 KMRX 112109
SVSMRX

Severe Weather Statement
National Weather Service Morristown TN
509 PM EDT Wed Aug 11 2021

TNC139-112118-
/O.CAN.KMRX.SV.W.0112.000000T0000Z-210811T2130Z/
Polk TN-
509 PM EDT Wed Aug 11 2021

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

LAT...LON 3524 8487 3532 8487 3541 8459 3527 8460
      3527 8467 3525 8469 3523 8472
TIME...MOT...LOC 2108Z 268DEG 11KT 3530 8472 

$$

TNC011-107-112130-
/O.CON.KMRX.SV.W.0112.000000T0000Z-210811T2130Z/
Bradley TN-McMinn TN-
509 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR NORTHEASTERN BRADLEY AND SOUTHWESTERN MCMINN COUNTIES...

At 508 PM EDT, a severe thunderstorm was located over Charleston, or
9 miles northwest of Benton, moving east at 15 mph.

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

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Charleston, Calhoun and Dentville. 

This includes Interstate 75 in Tennessee between mile markers 29 and
39.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3524 8487 3532 8487 3541 8459 3527 8460
      3527 8467 3525 8469 3523 8472
TIME...MOT...LOC 2108Z 268DEG 11KT 3530 8472 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BW

173 
WWUS54 KMRX 112129
SVSMRX

Severe Weather Statement
National Weather Service Morristown TN
529 PM EDT Wed Aug 11 2021

TNC011-107-112138-
/O.EXP.KMRX.SV.W.0112.000000T0000Z-210811T2130Z/
Bradley TN-McMinn TN-
529 PM EDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BRADLEY AND
SOUTHWESTERN MCMINN COUNTIES WILL EXPIRE AT 530 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.  However small
hail, gusty winds and heavy rain are still possible with this
thunderstorm.

Remember, a Severe Thunderstorm Warning still remains in effect for 
southeastern McMinn County until 615 PM EDT. 

LAT...LON 3524 8487 3532 8487 3541 8459 3527 8460
      3527 8467 3525 8469 3523 8472
TIME...MOT...LOC 2128Z 267DEG 12KT 3530 8464 

$$

BW

AREA FORECAST DISCUSSION
National Weather Service Morristown TN
311 PM EDT Wed Aug 11 2021

.SHORT TERM (Today through Tomorrow)...

Key Message:

1. Isolated to scattered showers and thunderstorms again today with
a few strong/severe storms possible with damaging winds being the
primary threat.

2. Above normal temperatures and elevated dewpoints will favor heat
indices in the upper 90s to lower 100s for the valley today.

Discussion:

Currently another day with showers and thunderstorms across the
Tennessee Valley and Cumberland Plateau. Environment is pretty much
persistence compared to yesterday with nearly zonal flow in the mid
levels and high pressure off the east coast allowing for southerly
winds and increased moisture from the Gulf to flow into the area.
Looking at radar this afternoon there are storms firing once again
along the higher terrain of the Cumberland Plateau and southern
Appalachian Mountains. Expect this to continue the rest of the
afternoon and into the evening. Over the remainder of the day these
storms should slide off the higher terrain and more into the Valley.
Model soundings indicate across the area indicate enough support to
see maybe a few isolated strong storms that could pose a brief wind
and heavy rain threat. Once again, think the biggest threat will be
strong winds as DCAPE values remain above 800 J/kg or higher.
Soundings indicate there is a bit better environment to possibly see
some hail with these storms as well with CAPE values in the hail
growth zone (-10 to -30 C) over 800 J/kg across the area. At this
time think that these strong to severe storms will be fairly
isolated, and hopefully not long lasting storms.

Surface observations are showing Heat Index values climbing into the
triple digits, mainly in the southern Valley. A few places will get
some relief from the heat with a rogue storm moving over them, but
overall expect most people today will complain more about the heat
rather than a thunderstorm over them. With today and the next
several days expected to see Heat Index values near or above triple
digits it's a good reminder to practice heat safety, especially in
the afternoon hours. It's a good idea to always carry water, be near
some shade, and to be able to recognize the signs of heat exhaustion.

As the sun starts to set the storms will begin to decrease in
coverage and strength. And once again fog will be possible early
tomorrow morning, especially in those places that receive moderate
to heavy rainfall this afternoon. Tomorrow we can expect a similar
weather situation with afternoon showers and thunderstorms and
temperatures within a degree or two of what we experience today. So
be prepared with an umbrella and bottle of water for tomorrow.

ABM

.LONG TERM...(Thursday night through Wednesday night)...

Key Messages:

1. Hot and humid conditions continues Friday and Saturday with
temperatures in the low 90s and heat indices in the 100 to 105
range.

2. Scattered showers and thunderstorms are expected each afternoon
with coverage increasing over the weekend through early next week.

3. Will be monitoring the track of TC Fred as it moves toward the SE
CONUS early next week with the potential for increased moisture
across the region.

Discussion:

Upper ridge across the SE CONUS will continue to bring an influx of
southerly moisture to the region with hot temperatures and humid
conditions into the weekend. A shortwave trough moving eastward
across the Great Lakes on Saturday will bring an associated cold
front southeastward toward the region on Saturday afternoon. This
will result in likely scattered showers and thunderstorms during the
afternoon. The GFS is indicating MLCAPE of 1000 to 1500 J/Kg, but
the NAM is much more bullish with instability showing MLCAPE of 2000
to 3000 J/Kg. Effective bulk shear remains weak around 15 kt. This
should limit overall convective organization with ordinary
convection, with some multicell clusters possible, being the likely
mode. If instability can be more along what the NAM is showing, some
strong to severe thunderstorms with isolated downburst winds would
be possible, but the overall risk is low. PW values will be near 1.8
to 2.0 inches with heavy rain rates possible.

This cold front will become stalled across the region on Saturday
night and Sunday with additional convection likely to develop in the
vicinity of this frontal boundary on Sunday afternoon. This front is
expected to wash out and potentially retreat northward early next
week with increasing moisture from the south. There is a lot of
uncertainty with the exact track of TC Fred, and the exact track of
this tropical remnant will have potential impacts on our weather. A
general increase in low-level moisture is expected as this system
moves toward the Southeast CONUS. However, a track to our east with
northerly flow along the western edge of the system would limit
precipitation coverage and chances. A center track closer to our
forecast area or just to our west would result in more widespread
convection with heavy precipitation possible. Current ensemble
spread is large for potential inland tracks, which is expected from
a broad, weak tropical system this far in advance.

It is forecast to remain warm and humid late weekend through the
middle of next week, but temperatures are forecast to be closer to
normal with increased cloud cover and lower heights.

JB

&&

.AVIATION...
18Z TAF DISCUSSION.

Another afternoon/evening with shower and thunderstorm chances
across the area. Have put TEMPO groups in during the time period
when the most widespread storms are expected. Storms could occur
outside of the TEMPO groups, but there should be much lower storm
coverage and therefore much lower chance of this occurring. Fog
is again possible at KTRI early tomorrow morning, but will wait to
see if moderate to heavy rain occurs at the airport before
dropping below MVFR conditions in the TAFs.

ABM

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             74  92  73  92  73 /  20  50  10  50  20
Knoxville McGhee Tyson Airport, TN  72  92  73  91  72 /  20  40  10  50  20
Oak Ridge, TN                       72  92  72  90  71 /  20  40  10  50  20
Tri Cities Airport, TN              69  90  70  90  69 /  20  50  10  50  30

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

Hazardous Weather Outlook
National Weather Service Morristown TN
250 PM EDT Wed Aug 11 2021

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-
005-006-008-121900-
Cherokee-Clay-Scott-Campbell-Claiborne-Hancock-Hawkins-Sullivan-
Johnson-Morgan-Anderson-Union-Grainger-Hamblen-Northwest Cocke-
Cocke Smoky Mountains-Northwest Greene-Southeast Greene-
Washington-Unicoi-Northwest Carter-Southeast Carter-Roane-Loudon-
Knox-Jefferson-Northwest Blount-Blount Smoky Mountains-
North Sevier-Sevier Smoky Mountains-Sequatchie-Bledsoe-Rhea-Meigs-
McMinn-Northwest Monroe-Southeast Monroe-Marion-Hamilton-Bradley-
West Polk-East Polk-Lee-Wise-Russell-
250 PM EDT Wed Aug 11 2021 /150 PM CDT Wed Aug 11 2021/

This Hazardous Weather Outlook is for portions of southwest North
Carolina...east Tennessee and southwest Virginia.

.DAY ONE...This Afternoon and Tonight

Isolated to scattered showers and thunderstorms will occur again
this afternoon. Some of these storms could be strong to severe
with damaging winds, cloud to ground lightning, and brief heavy
rainfall being the primary threats.

In addition to the thunderstorms, heat indices will elevate into
the upper 90s for much of the northern Tennessee Valley today,
with values into the lower 100s across the central and southern
Tennessee Valley.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Afternoon heat indices will remain in the upper 90s to lower 100s
each afternoon on Thursday and Friday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not needed at this time.

Special Weather Statement
National Weather Service Morristown TN
359 PM EDT Wed Aug 11 2021

TNZ035-067-112030-
Roane TN-Morgan TN-
359 PM EDT Wed Aug 11 2021

...A strong thunderstorm will impact portions of south central Morgan
and central Roane Counties through 430 PM EDT...

At 357 PM EDT, Doppler radar was tracking a strong thunderstorm near
Rockwood, moving east at 20 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Kingston, Rockwood, Wartburg, Midtown, Harriman, Oakdale, Pine
Orchard and Frozen Head State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3587 8472 3589 8471 3590 8468 3591 8468
      3599 8472 3602 8475 3614 8453 3587 8450
      3586 8473
TIME...MOT...LOC 1957Z 254DEG 19KT 3594 8471

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

BW

Special Weather Statement
National Weather Service Morristown TN
409 PM EDT Wed Aug 11 2021

TNZ084-099-112045-
Hamilton TN-Meigs TN-
409 PM EDT Wed Aug 11 2021

...A strong thunderstorm will impact portions of southwestern Meigs
and northeastern Hamilton Counties through 445 PM EDT...

At 408 PM EDT, Doppler radar was tracking a strong thunderstorm near
Soddy-Daisy, or 12 miles northwest of Cleveland, moving east at 10
mph.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Soddy-Daisy, Lakesite, Birchwood, Shady Grove, Sale Creek, Flat Top
Mountain and Harrison Bay State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3532 8517 3542 8497 3530 8493 3530 8494
      3528 8494 3526 8497 3525 8496 3521 8499
      3520 8512
TIME...MOT...LOC 2008Z 249DEG 7KT 3529 8506

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

BW

Special Weather Statement
National Weather Service Morristown TN
411 PM EDT Wed Aug 11 2021

TNZ067-083-112045-
Rhea TN-Roane TN-
411 PM EDT Wed Aug 11 2021

...A strong thunderstorm will impact portions of northeastern Rhea
and west central Roane Counties through 445 PM EDT...

At 411 PM EDT, Doppler radar was tracking a strong thunderstorm near
Rockwood, moving east at 10 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Rockwood and Eagle Furnace.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3579 8487 3583 8480 3582 8478 3586 8473
      3590 8471 3590 8468 3592 8467 3593 8464
      3577 8462 3576 8487
TIME...MOT...LOC 2011Z 254DEG 10KT 3584 8478

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

BW

Special Weather Statement
National Weather Service Morristown TN
419 PM EDT Wed Aug 11 2021

TNZ085-086-112045-
Northwest Monroe TN-McMinn TN-
419 PM EDT Wed Aug 11 2021

...A strong thunderstorm will impact portions of northeastern McMinn
County through 445 PM EDT...

At 419 PM EDT, Doppler radar was tracking a strong thunderstorm near
Athens, moving southeast at 10 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Athens, Madisonville, Englewood, Niota and Clear Water.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3553 8467 3558 8455 3551 8435 3535 8458
TIME...MOT...LOC 2019Z 314DEG 7KT 3550 8454

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

BW

Special Weather Statement
National Weather Service Morristown TN
430 PM EDT Wed Aug 11 2021

TNZ084-085-099-100-112100-
Bradley TN-Hamilton TN-Meigs TN-McMinn TN-
430 PM EDT Wed Aug 11 2021

...A strong thunderstorm will impact portions of northern Bradley,
southwestern Meigs, southwestern McMinn and northeastern Hamilton
Counties through 500 PM EDT...

At 429 PM EDT, Doppler radar was tracking a strong thunderstorm 9
miles west of Charleston, or 9 miles north of Cleveland, moving east
at 5 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Cleveland, Charleston, Calhoun, Hillsview, Hopewell, Birchwood, Big
Spring, Tasso and Sale Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3521 8501 3538 8507 3546 8475 3519 8472
TIME...MOT...LOC 2029Z 263DEG 6KT 3531 8492

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

BW

Special Weather Statement
National Weather Service Morristown TN
432 PM EDT Wed Aug 11 2021

TNZ035-067-112100-
Roane TN-Morgan TN-
432 PM EDT Wed Aug 11 2021

...A strong thunderstorm will impact portions of south central Morgan
and north central Roane Counties through 500 PM EDT...

At 432 PM EDT, Doppler radar was tracking a strong thunderstorm 7
miles south of Wartburg, moving east at 10 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Wartburg, Harriman, Oakdale, Pine Orchard, Dearmond, Frozen Head
State Park and Coalfield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

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

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3592 8467 3605 8469 3616 8450 3589 8448
TIME...MOT...LOC 2032Z 266DEG 7KT 3599 8461

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

BW