Alert archive / Tennessee / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 23, NWS Nashville, TN

January 11, 2020Macon County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Jan 11, 2020, 6:26 PM CST for Macon County, Tennessee. It was in force for 34 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: Jan 11, 2020, 6:26 PM CST (00:26 UTC)
Expired: Jan 11, 2020, 7:00 PM CST
In force: 34 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Macon County, TN

The radar

The Nashville radar (KOHX), 63 km from the middle of the area, began a volume at 00:30 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

Time	Report	Where	Remark
Jan 11, 6:27 PM CST	TSTM WND DMG	4 Wnw Lafayette, TN	AT LEAST 15 TREES BLOWN DOWN ON FOX RUN LANE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 1 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 0.4 hours before the alert went out and 74 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: 42 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 771 m above ground
0-6 km bulk shear: 101 kt
0-1 km storm-relative helicity: 140 m²/s²
0-3 km storm-relative helicity: 137 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

371 
WUUS54 KOHX 120026
SVROHX
TNC111-120100-
/O.NEW.KOHX.SV.W.0023.200112T0026Z-200112T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Nashville TN
626 PM CST Sat Jan 11 2020

The National Weather Service in Nashville has issued a

* Severe Thunderstorm Warning for...
  Northern Macon County in Middle Tennessee...

* Until 700 PM CST.

* At 626 PM CST, a severe thunderstorm was located near Lafayette,
  moving east at 45 mph.

  HAZARD...60-65 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Lafayette and Red Boiling Springs. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3662 8579 3661 8580 3654 8581 3652 8621
      3653 8622 3661 8621 3664 8620
TIME...MOT...LOC 0026Z 264DEG 38KT 3657 8612 

HAIL...<.75IN
WIND...60MPH
 
$$

27

1 follow-up statement

689 
WWUS54 KOHX 120044
SVSOHX

Severe Weather Statement
National Weather Service Nashville TN
644 PM CST Sat Jan 11 2020

TNC111-120100-
/O.CON.KOHX.SV.W.0023.000000T0000Z-200112T0100Z/
Macon TN-
644 PM CST Sat Jan 11 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM CST
FOR NORTHEASTERN MACON COUNTY...

At 644 PM CST, a severe thunderstorm was located near Red Boiling
Springs, or 9 miles northeast of Lafayette, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Lafayette and Red Boiling Springs. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3662 8579 3661 8580 3654 8581 3653 8605
      3663 8602
TIME...MOT...LOC 0044Z 264DEG 38KT 3659 8588 

HAIL...<.75IN
WIND...60MPH
 
$$

27

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 Nashville, TN wrote its last area forecast discussion before this severe thunderstorm warning went out at Jan 11, 5:27 PM CST, 59 minutes earlier.

Area forecast discussion, Jan 11, 5:27 PM CST, 59 minutes before

Area Forecast Discussion
National Weather Service Nashville TN
527 PM CST Sat Jan 11 2020

.UPDATE...
FOR 00Z AVIATION DISCUSSION.

&&

.DISCUSSION...

Back edge of the precipitation shield now extends from CKV southward
through Waynesboro. The main line of tstms is now working across the
Plateau. The tornado watch remains in effect for our far
southeastern counties through 8 pm. Although, it appears that that
watch will likely be cancelled once the line clears our area, in a
couple of hours from now. Still looking at isol thunder to the west
of the main line. Helicity values still remain elevated in that se
corner, so we are not out of the woods just yet.

It looks as though the convection should end across our Plateau
around 8 pm or so. Will definitely utilize the option to include a
pre first period giving the ramping down nature of the activity.

Otw, clouds to persist overnight. As for the wind advisory, a few of
the models still lean toward some subsidence as the rain shuts off.
this could mix down some higher winds again late this afternoon.
Thus, the plan will be to allow the wind advisory to continue
through 00Z as planned.

Moving on, the upcoming replacement airmass will be colder than it
has been. However, we are still looking at above normal
temperatures. Southerly upper level component will remain active and
thus, shower activity will lift back to the north by Monday night.
Additionally, we will have enough instability for tstm inclusion.
The active weather will stick around through Wednesday when a
stronger cold front approaches. The good news is that qpf amounts
dont look to be too worrisome. Maybe a half inch or so from Mon nt
through Wed.

High temps by late in the week will fall to near normal levels. This
will be short lived however as a frontal boundary takes aim on the
mid state by saturday with the sfc energy being focused well to our
north.

&&

.AVIATION...
00Z TAF DISCUSSION.

A thin line of showers moving across Middle TN at issuance could
cause brief gusty winds to 35 kts at KBNA/KMQY in the next hour.

Otherwise, look for mainly MVFR conditions overnight with
possibly some IFR around sunrise. Clouds should start to clear out
by late morning and while I haven't indicated this in this set of
TAFs, will wait for this evening's suite of models to come in.

Winds will remain breezy until around midnight when 5-10 kts will
become more common. Wind shift will also occur overnight as the
actual front pushes through Middle TN.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

DISCUSSION......21
AVIATION........Unger

Hazardous weather outlook, Jan 11, 4:14 PM CST, 2 hours 12 minutes before

Hazardous Weather Outlook
National Weather Service Nashville TN
414 PM CST Sat Jan 11 2020

TNZ005>011-023>034-056>066-075-077>080-093>095-122215-
Stewart-Montgomery-Robertson-Sumner-Macon-Clay-Pickett-Houston-
Humphreys-Dickson-Cheatham-Davidson-Wilson-Trousdale-Smith-
Jackson-Putnam-Overton-Fentress-Perry-Hickman-Lewis-Williamson-
Maury-Marshall-Rutherford-Cannon-De Kalb-White-Cumberland-Bedford-
Coffee-Warren-Grundy-Van Buren-Wayne-Lawrence-Giles-
414 PM CST Sat Jan 11 2020

This Hazardous Weather Outlook is for portions of Middle
Tennessee.

.DAY ONE...Tonight.

Rises on areas waterways are likely as today's rainfall runs off
into rivers and streams, however no significant flooding is
expected.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

27

In the hours before

Local storm report, Jan 11, 2:30 PM CST, 3 hours 56 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
230 PM CST SAT JAN 11 2020

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

0834 AM     TSTM WND DMG     SPRINGFIELD             36.50N  86.88W
01/11/2020                   ROBERTSON          TN   911 CALL CENTER

            TREES DOWN ACROSS THE CITY. ONE TREE FELL ON A HOME BUT
            THE HOME DID NOT SUSTAIN DAMAGE.

&&

EVENT NUMBER OHX2000021

SCHAPER

Special weather statement, Jan 11, 3:16 PM CST, 3 hours 10 minutes before

Special Weather Statement
National Weather Service Nashville TN
316 PM CST Sat Jan 11 2020

TNZ066-112145-
Cumberland TN-
316 PM CST Sat Jan 11 2020

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN CUMBERLAND COUNTY UNTIL
345 PM CST...

At 316 PM CST, Doppler radar was tracking a strong thunderstorm near
Fairfield Glade, or 9 miles east of Crossville, moving east at 40
mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Crossville, Fairfield Glade, Crab Orchard and Cumberland Mountain
State Park.

This includes Interstate 40 between mile markers 323 and 339.

A Tornado Watch remains in effect until 800 PM CST for Middle
Tennessee.

LAT...LON 3590 8471 3586 8473 3583 8477 3582 8480
      3576 8492 3577 8493 3575 8503 3577 8504
      3614 8494 3614 8487 3608 8483 3609 8483
      3609 8480 3605 8479 3600 8472 3591 8468
TIME...MOT...LOC 2116Z 261DEG 36KT 3592 8487

Whitehead

Local storm report, Jan 11, 3:34 PM CST, 2 hours 52 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
334 PM CST SAT JAN 11 2020

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

0227 PM     TSTM WND DMG     PALMER                  35.36N  85.57W
01/11/2020                   GRUNDY             TN   911 CALL CENTER

            TREES AND POWER LINES DOWN IN NORTH-CENTRAL AND EASTERN
            PORTIONS OF THE COUNTY.

&&

EVENT NUMBER OHX2000022

SCHAPER

Special weather statement, Jan 11, 5:19 PM CST, 1 hour 7 minutes before

Special Weather Statement
National Weather Service Nashville TN
519 PM CST Sat Jan 11 2020

TNZ007-008-026-027-120000-
Robertson TN-Davidson TN-Cheatham TN-Sumner TN-
519 PM CST Sat Jan 11 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN DAVIDSON...SUMNER...
NORTHEASTERN CHEATHAM AND ROBERTSON COUNTIES UNTIL 600 PM CST...

At 519 PM CST, Doppler radar was tracking a strong thunderstorm near
Coopertown, or 9 miles north of Ashland City, moving northeast at 50
mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Gallatin, Springfield, Ashland City, Hendersonville, Goodlettsville,
White House, Millersville, Greenbrier, Coopertown, Ridgetop, Cross
Plains, Portland, Joelton, Pleasant View, Orlinda, Adams, Cedar Hill,
Mitchellville, Bledsoe Creek State Park and Cottontown.

This includes the following highways...
 Interstate 65 between mile markers 95 and 121.
 Interstate 24 between mile markers 18 and 41.

LAT...LON 3665 8633 3639 8629 3620 8710 3645 8713
      3646 8712 3646 8713 3652 8711 3655 8712
      3656 8714 3665 8694 3665 8659 3663 8656
      3665 8651
TIME...MOT...LOC 2319Z 242DEG 42KT 3641 8703

27

Special weather statement, Jan 11, 5:36 PM CST, 50 minutes before

Special Weather Statement
National Weather Service Nashville TN
536 PM CST Sat Jan 11 2020

TNZ027-028-059-062-120015-
Rutherford TN-Williamson TN-Davidson TN-Wilson TN-
536 PM CST Sat Jan 11 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN DAVIDSON...NORTHWESTERN
RUTHERFORD...NORTHEASTERN WILLIAMSON AND WESTERN WILSON COUNTIES
UNTIL 615 PM CST...

At 536 PM CST, Doppler radar was tracking a strong thunderstorm over
Franklin, moving northeast at 50 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Franklin, Lebanon, Smyrna, Brentwood, La Vergne, Mount Juliet,
Nolensville, Forest Hills, Oak Hill, Belle Meade, Thompson's Station,
Walterhill, Rural Hill, Bellevue, Antioch, Belinda City, Berry Hill,
Cedars Of Lebanon State Park, Percy Priest Lake and Gladeville.

This includes the following highways...
 Interstate 40 between mile markers 212 and 239.
 Interstate 65 between mile markers 60 and 82.
 Interstate 24 between mile markers 52 and 71.
 Interstate 840 between mile markers 25 and 30, and between mile
markers 58 and 76.

LAT...LON 3598 8626 3579 8696 3609 8694 3631 8627
TIME...MOT...LOC 2336Z 244DEG 45KT 3596 8688

27

Special weather statement, Jan 11, 6:12 PM CST, 14 minutes before

Special Weather Statement
National Weather Service Nashville TN
612 PM CST Sat Jan 11 2020

TNZ028-030-062-064-120100-
Rutherford TN-Wilson TN-De Kalb TN-Smith TN-
612 PM CST Sat Jan 11 2020

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN SMITH...NORTHWESTERN DE
KALB...NORTHEASTERN RUTHERFORD AND SOUTHERN WILSON COUNTIES UNTIL 700
PM CST...

At 611 PM CST, Doppler radar was tracking a strong thunderstorm near
Walterhill, or 12 miles southwest of Lebanon, moving east at 50 mph.

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

Locations impacted include...
Lebanon, Smyrna, Mount Juliet, Watertown, Gordonsville, Walterhill,
Belinda City, Hickman, South Carthage, Alexandria, Dowelltown,
Liberty, Tuckers Crossroads, Cedars Of Lebanon State Park, Center
Hill Lake, Edgar Evans State Park and Gladeville.

This includes the following highways...
 Interstate 40 between mile markers 228 and 266.
 Interstate 840 between mile markers 58 and 76.

LAT...LON 3594 8648 3620 8648 3624 8582 3600 8579
TIME...MOT...LOC 0011Z 255DEG 44KT 3605 8642

27

The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 11, 6:09 PM CST	Severe Thunderstorm Warning	OHX	Macon, Smith, Sumner, Trousdale, Wilson	36 min
Jan 11, 6:12 PM CST	Special Weather Statement	OHX	Wilson	48 min
Jan 11, 6:20 PM CST	Severe Thunderstorm Warning	OHX	Cannon, DeKalb, Rutherford, Smith, Wilson	40 min
Jan 11, 6:42 PM CST	Severe Thunderstorm Warning	OHX	Clay, Jackson, Macon, Smith, Trousdale	48 min
Jan 11, 6:55 PM CST	Severe Thunderstorm Warning	OHX	DeKalb, Jackson, Overton, Putnam, Smith	35 min
Jan 11, 7:29 PM CST	Special Weather Statement	OHX	Clay, Overton, Putnam	46 min
Jan 11, 7:50 PM CST	Special Weather Statement	OHX	Cumberland, Fentress, Pickett	40 min
Jan 11, 7:53 PM CST	River Flood Advisory	OHX	Perry	51 hr
Jan 12, 1:35 AM CST	River Flood Warning	OHX	Lawrence	5 hr
Jan 12, 4:35 AM CST	River Flood Advisory	OHX	Hickman	46 hr
Jan 12, 6:17 AM CST	River Flood Advisory	OHX	Lawrence	4 hr
Jan 12, 2:32 PM CST	River Flood Advisory	OHX	Davidson	8 days
Jan 12, 2:38 PM CST	River Flood Advisory	OHX	Sumner, Trousdale, Wilson	31 hr
Jan 12, 3:31 PM CST	River Flood Advisory	OHX	Humphreys	45 hr

Nearby

Severe Thunderstorm Warnings in Tennessee, 2020 Every severe thunderstorm warning in 2020

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.