EF0 tornado, Nash to Twin Oak, Tennessee, August 28, 2020

1. EF065 to 85 mphthis tornado

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF0

Date

August 28, 2020

Touchdown

7:24 PM CDT (00:24 UTC)

Lifted

7:28 PM CDT (00:28 UTC)

On the ground

4 minutes

Path length

2.4 miles (3.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$15,000

County

Putnam County

Touchdown point

36.075, -85.641

Lift-off point

36.102, -85.614

Record number

2008281824-01

11 damage points were recorded along this path by NWS OHX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 75 mph.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

After making landfall in southwest Louisiana on Wednesday, August 26, 2020, Hurricane Laura moved northward into Arkansas and weakened to a tropical storm on Thursday, August 27, then traveled eastward across Tennessee and Kentucky and weakened further to a tropical depression on Friday, August 28. The system brought numerous showers and thunderstorms to Middle Tennessee, some of which became severe and produced several reports of damaging winds along with two weak tornadoes. Rainfall totals across the area ranged from 1 to 3 inches.

A damage survey by Putnam County EMA along with radar data indicate a brief EF-0 tornado touched down south of Baxter. One home on Palmer Lane suffered garage door damage near the start of the path and a mobile home lost part of its roof on Thomas Twin Oak Road at Palmer Lane. A barn was damaged on Moss Road north of Alton Boyd Road. Several trees were snapped and uprooted along the intermittent damage path. Additional minor wind damage including snapped tree branches and minor exterior damage to a greenhouse occurred further to the northeast along Ditty Road and Cowan Road, but the damage was too minor to be certain if this was part of the tornado path. This is the first known tornado to occur in Putnam County in the month of August.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 20:00 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Sparta (SRB), 9 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Nashville radar (KOHX), 86 km away, was scanning. The volume nearest the touchdown began at 00:24 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2020 tornado in TennesseeEvery tornado in Tennessee since 1950Warnings in force in Tennessee nowThe forecast where you are

12 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.