Alert archive / Tennessee / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 133, NWS Nashville, TN

August 18, 2021Davidson County, Rutherford County, Williamson County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Aug 18, 2021, 6:28 PM CDT for Davidson County, Rutherford County, Williamson County, Tennessee. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 18, 2021, 6:28 PM CDT (23:28 UTC)
Expired: Aug 18, 2021, 7:00 PM CDT
In force: 32 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Davidson County, TN, Rutherford County, TN, Williamson County, TN

The radar

The Nashville radar (KOHX), 38 km from the middle of the area, began a volume at 23:29 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, 11.5 hours before the alert went out and 24 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: 259 J/kg
Mixed-layer CIN: -49 J/kg
Mixed-layer LCL: 919 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 70 m²/s²
0-3 km storm-relative helicity: 72 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

803 
WUUS54 KOHX 182328
SVROHX
TNC037-149-187-190000-
/O.NEW.KOHX.SV.W.0133.210818T2328Z-210819T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Nashville TN
628 PM CDT Wed Aug 18 2021

The National Weather Service in Nashville has issued a

* Severe Thunderstorm Warning for...
  Southeastern Davidson County in Middle Tennessee...
  Northwestern Rutherford County in Middle Tennessee...
  Eastern Williamson County in Middle Tennessee...

* Until 700 PM CDT.

* At 628 PM CDT, a severe thunderstorm was located near Franklin,
  moving northeast at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Franklin, Smyrna, Brentwood, La Vergne, Nolensville, Antioch and
  Triune.

This includes the following highways...
 Interstate 65 between mile markers 62 and 73.
 Interstate 24 between mile markers 57 and 74.
 Interstate 840 between mile markers 34 and 48.

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 3578 8675 3591 8689 3600 8684 3609 8667
      3604 8651 3589 8647
TIME...MOT...LOC 2328Z 228DEG 20KT 3590 8675 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

13

1 follow-up statement

524 
WWUS54 KOHX 182355
SVSOHX

Severe Weather Statement
National Weather Service Nashville TN
655 PM CDT Wed Aug 18 2021

TNC037-149-187-190005-
/O.EXP.KOHX.SV.W.0133.000000T0000Z-210819T0000Z/
Davidson TN-Rutherford TN-Williamson TN-
655 PM CDT Wed Aug 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN DAVIDSON...
NORTHWESTERN RUTHERFORD AND EASTERN WILLIAMSON COUNTIES WILL EXPIRE
AT 700 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 3578 8675 3591 8689 3600 8684 3609 8667
      3604 8651 3589 8647
TIME...MOT...LOC 2355Z 228DEG 20KT 3599 8662 

$$

13

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 12:06 PM CDT	Special Weather Statement	OHX	Wilson	39 min
Aug 18, 1:52 PM CDT	Special Weather Statement	OHX	Wilson	38 min
Aug 18, 2:24 PM CDT	Areal Flood Advisory	OHX	Davidson, Sumner, Wilson	2 hr
Aug 18, 2:33 PM CDT	Flash Flood Warning	OHX	Davidson, Sumner, Wilson	117 min
Aug 18, 2:59 PM CDT	Special Weather Statement	OHX	Sumner	31 min
Aug 18, 3:38 PM CDT	Special Weather Statement	OHX	Lewis	52 min
Aug 18, 3:40 PM CDT	Special Weather Statement	OHX	Cheatham	35 min
Aug 18, 3:57 PM CDT	Special Weather Statement	OHX	Robertson	48 min
Aug 18, 3:58 PM CDT	Special Weather Statement	OHX	Dickson	47 min
Aug 18, 4:00 PM CDT	Areal Flood Advisory	OHX	Cheatham, Davidson, Dickson, Montgomery, Robertson	3 hr
Aug 18, 4:02 PM CDT	Areal Flood Advisory	OHX	Lawrence, Lewis, Perry, Wayne	3 hr
Aug 18, 4:16 PM CDT	Special Weather Statement	OHX	Lewis	44 min
Aug 18, 4:24 PM CDT	Special Weather Statement	OHX	Montgomery, Robertson	51 min
Aug 18, 4:25 PM CDT	Special Weather Statement	OHX	Overton	50 min
Aug 18, 4:43 PM CDT	Areal Flood Advisory	OHX	Fentress, Overton, Putnam	2 hr
Aug 18, 4:52 PM CDT	Special Weather Statement	OHX	Maury	53 min
Aug 18, 5:13 PM CDT	Flash Flood Warning	OHX	Lawrence, Wayne	3 hr
Aug 18, 5:27 PM CDT	Areal Flood Advisory	OHX	Fentress	2 hr
Aug 18, 5:41 PM CDT	Special Weather Statement	OHX	Davidson, Maury, Williamson	49 min
Aug 18, 6:08 PM CDT	Areal Flood Advisory	OHX	Bedford, Davidson, Marshall, Maury, Rutherford, Williamson	112 min
Aug 18, 6:15 PM CDT	Special Weather Statement	OHX	Giles	45 min
Aug 18, 6:17 PM CDT	Areal Flood Advisory	OHX	Giles, Lawrence, Marshall	58 min
Aug 18, 6:48 PM CDT	Special Weather Statement	OHX	Wilson	42 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2021 Every severe thunderstorm warning in 2021

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.