Alert archive / Tennessee / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 16, NWS Morristown, TN

April 17, 2013Morgan County, Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at Apr 17, 2013, 1:20 PM EDT for Morgan County, Tennessee. It was in force for 55 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 17, 2013, 1:20 PM EDT (17:20 UTC)
Expired: Apr 17, 2013, 2:15 PM EDT
In force: 55 min
Issued by: NWS Morristown, TN
Area: Storm-based polygon

County Morgan County, TN

The radar

The Knoxville radar (KMRX), 112 km from the middle of the area, began a volume at 17:20 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 12:00Z, 5.3 hours before the alert went out and 175 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: 1987 J/kg
Mixed-layer CIN: -28 J/kg
Mixed-layer LCL: 747 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 130 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 3.7

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 17, 9:40 AM EDT, 3 hours 40 minutes earlier.

Area forecast discussion, Apr 17, 9:40 AM EDT, 3 hours 40 minutes before

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Hazardous weather outlook, Apr 17, 3:34 AM EDT, 9 hours 46 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MORRISTOWN TN
334 AM EDT WED APR 17 2013

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-
005-006-008-180745-
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-
334 AM EDT WED APR 17 2013 /234 AM CDT WED APR 17 2013/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST NORTH
CAROLINA...EAST TENNESSEE AND SOUTHWEST VIRGINIA.

.DAY ONE...TODAY AND TONIGHT...

SCATTERED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL BE
AROUND THE AREA TODAY. A FEW STORMS MAY BECOME RATHER STRONG EVEN
EARLY THIS MORNING ACROSS NORTHEAST TENNESSEE WITH MORE DEVELOPMENT
EXPECTED DURING THE PEAK HEATING OF THE AFTERNOON. AN ISOLATED
STRONG TO MARGINALLY SEVERE STORM IS POSSIBLE...WITH DAMAGING WINDS
AND HAIL UP TO 1 INCH DIAMETER THE POTENTIAL THREATS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

A COLD FRONT WILL BRING A LINE OF THUNDERSTORMS ACROSS THE AREA
LATE THURSDAY NIGHT THROUGH FRIDAY MORNING. THERE IS A POTENTIAL
FOR SOME SEVERE STORMS...WITH DAMAGING WIND GUSTS BEING THE MAIN
THREAT.

OTHERWISE...NO HAZARDOUS WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS UNLIKELY AT THIS TIME.

In the hours before

Special weather statement, Apr 17, 11:58 AM EDT, 1 hour 22 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1158 AM EDT WED APR 17 2013

TNZ012-171645-
SCOTT TN-
1158 AM EDT WED APR 17 2013

...SIGNIFICANT WEATHER ADVISORY FOR SCOTT COUNTY UNTIL 1245 PM EDT...

AT 1153 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A STRONG THUNDERSTORM 9 MILES WEST OF ONEIDA...MOVING EAST AT 15 MPH.

SMALL HAIL AND WIND GUSTS IN EXCESS OF 40 MPH ARE POSSIBLE WITH THIS
STORM.

LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...ONEIDA...
HUNTSVILLE...ELGIN...WINFIELD...SLICK ROCK AND KETCHEN.

IN ADDITION TO SMALL HAIL AND GUSTY WINDS...FREQUENT CLOUD TO GROUND
LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY!
LIGHTNING IS ONE OF NATURES PRIMARY KILLERS ASSOCIATED WITH
THUNDERSTORMS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

Special weather statement, Apr 17, 12:36 PM EDT, 44 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1236 PM EDT WED APR 17 2013

TNZ035-171715-
MORGAN TN-
1236 PM EDT WED APR 17 2013

...SIGNIFICANT WEATHER ADVISORY FOR MORGAN COUNTY UNTIL 115 PM...

AT 1231 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A CLUSTER OF STRONG THUNDERSTORMS ALONG THE MORGAN AND FENTRESS
COUNTY LINE...WHICH WERE MOVING SOUTHEAST AT 15 MPH.

SMALL HAIL AND WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THESE STORMS.

IN ADDITION TO SMALL HAIL AND GUSTY WINDS...FREQUENT CLOUD TO GROUND
LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY!
LIGHTNING IS ONE OF NATURES PRIMARY KILLERS ASSOCIATED WITH
THUNDERSTORMS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

DMG

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 17, 1:11 PM EDT	Areal Flood Advisory	MRX	Morgan	3 hr
Apr 17, 1:37 PM EDT	Flash Flood Warning	MRX	Morgan	3 hr
Apr 17, 1:58 PM EDT	Severe Thunderstorm Warning	MRX	Bledsoe	62 min
Apr 17, 2:21 PM EDT	Areal Flood Advisory	MRX	Bledsoe	3 hr
Apr 17, 2:29 PM EDT	Severe Thunderstorm Warning	MRX	Meigs, Rhea	61 min
Apr 17, 2:52 PM EDT	Flash Flood Warning	MRX	Bledsoe	3 hr
Apr 17, 3:25 PM EDT	Severe Thunderstorm Warning	MRX	Bledsoe	65 min
Apr 17, 3:44 PM EDT	Areal Flood Advisory	MRX	McMinn, Meigs	3 hr
Apr 17, 3:49 PM EDT	Areal Flood Advisory	MRX	McMinn, Meigs	3 hr
Apr 17, 4:26 PM EDT	Severe Thunderstorm Warning	MRX	Marion, Sequatchie	64 min
Apr 17, 4:55 PM EDT	Areal Flood Advisory	MRX	Marion, Sequatchie	3 hr
Apr 17, 5:34 PM EDT	Areal Flood Advisory	MRX	Bradley, Hamilton	3 hr
Apr 17, 7:04 PM EDT	Areal Flood Advisory	MRX	Marion	3 hr
Apr 17, 10:08 AM EDT	Areal Flood Advisory	MRX	Lee, Scott	3 hr
Apr 17, 11:43 AM EDT	Areal Flood Advisory	MRX	Wise, City of Norton	2 hr
Apr 17, 4:30 PM EDT	Severe Thunderstorm Warning	MRX	Cherokee	60 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2013 Every severe thunderstorm warning in 2013

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.