Alert archive / Tennessee / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 22, NWS Morristown, TN

April 20, 20154 counties in Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at Apr 20, 2015, 2:44 AM CDT for 4 counties in Tennessee. It was in force for 46 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: Apr 20, 2015, 2:44 AM CDT (07:44 UTC)
Expired: Apr 20, 2015, 3:30 AM CDT
In force: 46 min
Issued by: NWS Morristown, TN
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Bledsoe County, TN, Hamilton County, TN, Marion County, TN, Sequatchie County, TN

The radar

The Northeast Alabama radar (KHTX), 79 km from the middle of the area, began a volume at 07:44 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 20, 1:09 AM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 7.7 hours before the alert went out and 144 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: 170 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 927 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 67 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

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 Apr 20, 1:50 AM CDT, 54 minutes earlier.

Area forecast discussion, Apr 20, 1:50 AM CDT, 54 minutes before

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Hazardous weather outlook, Apr 20, 1:44 AM CDT, 1 hour before

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In the hours before

Local storm report, Apr 19, 9:03 PM CDT, 5 hours 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1003 PM EDT SUN APR 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0915 PM     TSTM WND DMG     MAYNARDVILLE            36.25N 83.81W
04/19/2015                   UNION              TN   911 CALL CENTER

            A FEW TREES AND POWER LINES DOWN ACROSS UNION COUNTY

&&

AMP

Special weather statement, Apr 19, 9:11 PM CDT, 5 hours 33 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1011 PM EDT SUN APR 19 2015

TNZ016-040>045-200300-
COCKE SMOKY MOUNTAINS TN-WASHINGTON TN-NORTHWEST COCKE TN-HAWKINS TN-
SOUTHEAST GREENE TN-UNICOI TN-NORTHWEST GREENE TN-
1011 PM EDT SUN APR 19 2015

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL COCKE...SOUTHERN
WASHINGTON...SOUTHWESTERN HAWKINS...UNICOI...GREENE AND SOUTHWESTERN
CARTER COUNTIES UNTIL 1100 PM EDT...

AT 1010 PM EDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM 9 MILES WEST OF GREENEVILLE
TO 25 MILES SOUTHEAST OF PARROTTSVILLE...AND MOVING EAST AT 45 MPH.

WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THESE STORMS.

LOCATIONS IMPACTED INCLUDE...
GREENEVILLE...ERWIN...TUSCULUM...BANNER HILL...UNICOI...MOSHEIM...
LIBERTY...EMBREEVILLE...CEDAR CREEK...CAMP CREEK...CHUCKY...LIMESTONE
COVE...ROUND MOUNTAIN...CANEY BRANCH...LIMESTONE...ROCKY FORK AND
MOHAWK.

LAT...LON 3613 8225 3614 8229 3611 8237 3601 8246
      3595 8256 3597 8261 3601 8261 3603 8259
      3607 8264 3600 8278 3593 8281 3595 8285
      3595 8290 3593 8292 3588 8290 3580 8296
      3625 8307 3622 8226 3615 8222
TIME...MOT...LOC 0210Z 255DEG 39KT 3620 8298 3569 8286

17

Local storm report, Apr 19, 9:24 PM CDT, 5 hours 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1024 PM EDT SUN APR 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1011 PM     TSTM WND DMG     ROGERSVILLE             36.41N 83.01W
04/19/2015                   HAWKINS            TN   911 CALL CENTER

            A FEW TREES AND POWER LINES DOWN IN ROGERSVILLE.

&&

AMP

Local storm report, Apr 19, 9:32 PM CDT, 5 hours 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1032 PM EDT SUN APR 19 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1028 PM     TSTM WND DMG     BAILEYTON               36.33N 82.83W
04/19/2015                   GREENE             TN   911 CALL CENTER

            TREES AND POWER LINES DOWN ACROSS GREENE COUNTY.

&&

AMP

Special weather statement, Apr 19, 9:44 PM CDT, 5 hours before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1044 PM EDT SUN APR 19 2015

TNZ017-018-044>047-VAZ005-200330-
WASHINGTON TN-JOHNSON TN-SULLIVAN TN-SOUTHEAST CARTER TN-
NORTHWEST CARTER TN-UNICOI TN-SCOTT VA-
1044 PM EDT SUN APR 19 2015

...SIGNIFICANT WEATHER ADVISORY FOR JOHNSON...EASTERN WASHINGTON...
UNICOI...CARTER...SULLIVAN...SOUTHWESTERN WASHINGTON...SOUTHEASTERN
SCOTT COUNTIES AND THE CITY OF BRISTOL UNTIL 1130 PM EDT...

AT 1043 PM EDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM NEAR KINGSPORT TO NEAR
BANNER HILL...AND MOVING EAST AT 45 MPH.

WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THESE STORMS.

LOCATIONS IMPACTED INCLUDE...
JOHNSON CITY...KINGSPORT...ELIZABETHTON...ERWIN...MOUNTAIN CITY...
BRISTOL TN...BRISTOL...JONESBOROUGH...MIDWAY...SPURGEON...OAK
GROVE...COLONIAL HEIGHTS...WALNUT HILL...CENTRAL...HAMPTON...BANNER
HILL...PINE CREST...GRAY...UNICOI AND BLUFF CITY.

LAT...LON 3653 8171 3647 8170 3641 8174 3634 8171
      3636 8179 3634 8185 3630 8191 3612 8203
      3610 8208 3611 8213 3615 8215 3616 8222
      3613 8225 3611 8237 3602 8245 3603 8252
      3663 8253 3665 8231 3660 8229 3661 8166
TIME...MOT...LOC 0243Z 271DEG 40KT 3656 8246 3610 8246

17

Local storm report, Apr 19, 11:27 PM CDT, 3 hours 17 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 19, 7:00 PM CDT	Special Weather Statement	MRX	Bradley, McMinn, Meigs, Polk, Rhea, Roane	45 min
Apr 19, 7:23 PM CDT	Severe Thunderstorm Warning	MRX	Loudon, McMinn, Monroe	37 min
Apr 19, 7:29 PM CDT	Special Weather Statement	MRX	Anderson, Knox, Loudon, Roane	46 min
Apr 19, 7:50 PM CDT	Severe Thunderstorm Warning	MRX	Anderson, Blount, Knox, Sevier	25 min
Apr 19, 8:03 PM CDT	Severe Thunderstorm Warning	MRX	Anderson, Campbell, Claiborne, Knox, Union	27 min
Apr 19, 8:15 PM CDT	Severe Thunderstorm Warning	MRX	Cocke, Grainger, Hamblen, Jefferson, Knox, Sevier and 1 more	30 min
Apr 19, 8:29 PM CDT	Severe Thunderstorm Warning	MRX	Claiborne, Grainger, Hamblen, Hancock, Hawkins, Union	31 min
Apr 19, 8:41 PM CDT	Severe Thunderstorm Warning	MRX	Cocke, Grainger, Greene, Hamblen, Hawkins, Jefferson and 1 more	34 min
Apr 19, 8:56 PM CDT	Severe Thunderstorm Warning	MRX	Greene, Hamblen, Hancock, Hawkins	34 min
Apr 19, 9:11 PM CDT	Special Weather Statement	MRX	Greene, Unicoi	49 min
Apr 19, 9:21 PM CDT	Severe Thunderstorm Warning	MRX	Greene, Hancock, Hawkins, Sullivan, Unicoi, Washington	24 min
Apr 19, 9:44 PM CDT	Special Weather Statement	MRX	Carter, Johnson, Sullivan, Unicoi, Washington	46 min
Apr 19, 10:11 PM CDT	Severe Thunderstorm Warning	MRX	Carter, Johnson, Sullivan	49 min
Apr 20, 3:29 AM CDT	Special Weather Statement	MRX	Bledsoe, Bradley, Hamilton, Meigs, Rhea	46 min
Apr 20, 4:08 AM CDT	Special Weather Statement	MRX	Anderson, Knox, Roane	67 min
Apr 20, 4:11 AM CDT	Special Weather Statement	MRX	Campbell	49 min
Apr 20, 4:15 AM CDT	Special Weather Statement	MRX	Bradley, McMinn, Meigs, Monroe, Polk	45 min
Apr 20, 4:50 AM CDT	Special Weather Statement	MRX	Blount, Monroe, Sevier	40 min
Apr 20, 4:58 AM CDT	Special Weather Statement	MRX	Grainger, Hamblen	47 min
Apr 20, 6:22 AM CDT	River Flood Warning	MRX	Cocke	9 hr
Apr 19, 9:00 PM CDT	Special Weather Statement	MRX	Lee, Wise, City of Norton	45 min
Apr 19, 9:30 PM CDT	Severe Thunderstorm Warning	MRX	Lee, Russell, Scott, Washington, Wise, City of Bristol and 1 more	45 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2015 Every severe thunderstorm warning in 2015

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.