Alert archive / Tennessee / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 106, NWS Morristown, TN

July 23, 2017Grainger County, Hamblen County, Jefferson County, Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at Jul 23, 2017, 10:16 PM EDT for Grainger County, Hamblen County, Jefferson County, Tennessee. It was in force for 44 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 23, 2017, 10:16 PM EDT (02:16 UTC)
Expired: Jul 23, 2017, 11:00 PM EDT
In force: 44 min
Issued by: NWS Morristown, TN
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Grainger County, TN, Hamblen County, TN, Jefferson County, TN

The radar

The Knoxville radar (KMRX), 2 km from the middle of the area, began a volume at 02:19 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.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 2.3 hours before the alert went out and 287 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: 2350 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 1310 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 20 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Morristown, TN wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 23, 7:25 PM EDT, 2 hours 51 minutes earlier.

Area forecast discussion, Jul 23, 7:25 PM EDT, 2 hours 51 minutes before

Area Forecast Discussion
National Weather Service Morristown TN
725 PM EDT Sun Jul 23 2017

.AVIATION...
Showers and thunderstorms are moving into the area. If/when they
impact an airport they will briefly cause degraded conditions
until they move out. Locations that get rainfall from
thunderstorms this afternoon could see fog overnight as well.

&&

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

ABM

Hazardous weather outlook, Jul 23, 3:24 PM EDT, 6 hours 52 minutes before

Hazardous Weather Outlook
National Weather Service Morristown TN
324 PM EDT Sun Jul 23 2017

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-
005-006-008-240900-
Cherokee-Clay-Scott TN-Campbell-Claiborne-Hancock-Hawkins-
Sullivan-Johnson-Morgan-Anderson-Union-Grainger-Hamblen-
Northwest Cocke-Cocke Smoky Mountains-Northwest Greene-
Southeast Greene-Washington TN-Unicoi-Northwest Carter-
Southeast Carter-Roane-Loudon-Knox-Jefferson-NW 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-Scott-Russell-Washington-
324 PM EDT Sun Jul 23 2017 /224 PM CDT Sun Jul 23 2017/

This Hazardous Weather Outlook is for portions of Southwest North
Carolina...East Tennessee and Southwest Virginia.

.DAY ONE...This Afternoon and Tonight

Scattered to numerous thunderstorms can be expected especially
this afternoon into early tonight, and a few of these storms may
become strong to severe, with damaging winds the primary threat.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter reports might be needed for parts of the area this evening.

In the hours before

Special weather statement, Jul 23, 9:08 PM EDT, 1 hour 8 minutes before

Special Weather Statement
National Weather Service Morristown TN
908 PM EDT SUN JUL 23 2017

TNZ012>014-036-037-240200-
Anderson TN-Claiborne TN-Union TN-Scott TN-Campbell TN-
908 PM EDT SUN JUL 23 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CLAIBORNE...
NORTHEASTERN ANDERSON...CAMPBELL...NORTHEASTERN SCOTT AND
NORTHWESTERN UNION COUNTIES UNTIL 1000 PM EDT...

At 908 PM EDT, Doppler radar was tracking a strong thunderstorm near
Zion Hill, or 12 miles northwest of La Follette, moving southeast at
40 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations impacted include...
Clinton, La Follette, Oneida, Jacksboro, Jellico, Caryville, Lake
City, Norris, Winfield, Norris Dam State Park, Elk Valley,
Andersonville, Big Ridge State Park, Sharps Chapel, Disney, Cove Lake
State Park, Ketchen, Indian Mountain State Park, Fincastle and Royal
Blue.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3659 8408 3640 8371 3618 8393 3618 8395
      3609 8406 3651 8455 3660 8441
TIME...MOT...LOC 0108Z 300DEG 33KT 3652 8427

EMH

Special weather statement, Jul 23, 9:12 PM EDT, 1 hour 4 minutes before

Special Weather Statement
National Weather Service Morristown TN
912 PM EDT SUN JUL 23 2017

TNZ015-016-VAZ001-005-240200-
Hancock TN-Hawkins TN-Scott VA-Lee VA-
912 PM EDT SUN JUL 23 2017

...SIGNIFICANT WEATHER ADVISORY FOR HAWKINS...HANCOCK...SOUTHEASTERN
LEE AND SOUTHWESTERN SCOTT COUNTIES UNTIL 1000 PM EDT...

At 911 PM EDT, Doppler radar was tracking a strong thunderstorm over
Smith, or 7 miles west of Jonesville, moving southeast at 40 mph.

Dime size hail and wind gusts up to 50 mph will be possible with this
storm.

Locations impacted include...
Rogersville, Sneedville, Jonesville, Surgoinsville, Church Hill,
Mount Carmel, Ewing, Okolona, Rose Hill, Kepler, Kyles Ford and
Pattonsville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3658 8263 3638 8277 3639 8278 3636 8281
      3637 8284 3635 8289 3660 8349 3667 8343
      3670 8334 3674 8320 3674 8314 3677 8313
TIME...MOT...LOC 0111Z 300DEG 33KT 3671 8324

EMH

Special weather statement, Jul 23, 9:27 PM EDT, 49 minutes before

Special Weather Statement
National Weather Service Morristown TN
927 PM EDT SUN JUL 23 2017

VAZ006-008-240215-
Washington VA-Russell VA-
927 PM EDT SUN JUL 23 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN RUSSELL AND
WASHINGTON COUNTIES UNTIL 1015 PM EDT...

At 926 PM EDT, Doppler radar was tracking a strong thunderstorm near
Cleveland Va, or 7 miles west of Lebanon, moving southeast at 40 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations impacted include...
Abingdon, Lebanon, Glade Spring, St. Paul, Damascus, Lindell,
Castlewood, Holston, Hansonville and Emory-Meadow View.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3661 8170 3662 8192 3660 8193 3659 8195
      3683 8238 3690 8233 3689 8232 3691 8232
      3690 8231 3691 8230 3693 8231 3698 8227
      3675 8168 3669 8165
TIME...MOT...LOC 0126Z 298DEG 35KT 3686 8220

EMH

Special weather statement, Jul 23, 9:40 PM EDT, 36 minutes before

Special Weather Statement
National Weather Service Morristown TN
940 PM EDT SUN JUL 23 2017

TNZ012-013-035-036-240230-
Anderson TN-Scott TN-Campbell TN-Morgan TN-
940 PM EDT SUN JUL 23 2017

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN MORGAN...NORTHWESTERN
ANDERSON...SOUTHWESTERN CAMPBELL AND SOUTHERN SCOTT COUNTIES UNTIL
1030 PM EDT...

At 940 PM EDT, Doppler radar was tracking a strong thunderstorm near
Huntsville, or 9 miles south of Oneida, moving southeast at 20 mph.

Wind gusts up to 50 mph will be possible with this storm.

Locations impacted include...
Oliver Springs, Huntsville, Helenwood, Sunbright, Rugby, Coalfield,
Smokey Junction, Rosedale, Robbins, Rugby State Park, Norma, Elgin,
Frozen Head State Park, Slick Rock and Petros.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3617 8411 3605 8434 3605 8436 3598 8447
      3599 8447 3633 8475 3634 8474 3635 8474
      3635 8473 3637 8473 3637 8470 3639 8469
      3640 8466 3645 8444
TIME...MOT...LOC 0140Z 326DEG 17KT 3637 8446

EMH

Special weather statement, Jul 23, 10:09 PM EDT, 7 minutes before

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Local storm report, Jul 23, 10:13 PM EDT, 3 minutes before

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  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 8:48 PM EDT	Special Weather Statement	MRX	Claiborne, Hancock	42 min
Jul 23, 9:08 PM EDT	Special Weather Statement	MRX	Campbell, Union	52 min
Jul 23, 9:12 PM EDT	Special Weather Statement	MRX	Hancock, Hawkins	48 min
Jul 23, 9:40 PM EDT	Special Weather Statement	MRX	Scott	50 min
Jul 23, 10:09 PM EDT	Special Weather Statement	MRX	Grainger, Hamblen, Jefferson	51 min
Jul 23, 10:44 PM EDT	Special Weather Statement	MRX	Jefferson	31 min
Jul 23, 11:37 PM EDT	Special Weather Statement	MRX	Cocke	23 min
Jul 24, 12:09 AM EDT	Special Weather Statement	MRX	Knox	51 min
Jul 24, 12:42 AM EDT	Special Weather Statement	MRX	Blount	48 min
Jul 24, 1:20 AM EDT	Special Weather Statement	MRX	Monroe	40 min
Jul 23, 8:40 PM EDT	Special Weather Statement	MRX	Scott	50 min
Jul 23, 9:27 PM EDT	Special Weather Statement	MRX	Washington	48 min
Jul 23, 9:56 PM EDT	Areal Flood Advisory	MRX	Russell, Washington	2 hr

Nearby

Severe Thunderstorm Warnings in Tennessee, 2017 Every severe thunderstorm warning in 2017

Sources

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