EF1 tornado, Oakton to Clinton, Kentucky, May 4, 2021

1. EF065 to 85 mph

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

2. EF186 to 110 mphthis tornado

   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

EF1

Date

May 4, 2021

Touchdown

3:31 AM CDT (08:31 UTC)

Lifted

3:38 AM CDT (08:38 UTC)

On the ground

7 minutes

Path length

5.3 miles (8.4 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

Property damage

$350,000

County

Hickman County

Touchdown point

36.661, -89.089

Lift-off point

36.670, -88.995

Record number

2105040231-01

40 damage points were recorded along this path by NWS MEG and NWS PAH, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 125 mph.

• Three outbuildings destroyed. Car moved 20 feet.
• Another tree nearby was damaged similarly.
• More damage along Levee Rd.
• Big trunk. Other smaller limbs broken in other trees in the vicinity. Inflow winds/gust front driven.

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

Clusters of storms, followed by a bowing line of thunderstorms, organized and accelerated east-northeastward during the overnight and wee morning hours. Several tornadoes accompanied mesovortices along the bowing line of storms. In addition, a particularly strong microburst was associated with the line. Finally, the occurrence of multiple thunderstorms resulted in localized flash flooding in the Pennyrile region. A mid-level shortwave trough moved east across the southern Plains. A belt of stronger southwesterly 500 mb winds spread northeast ahead of the trough into southeast Missouri and Arkansas. Instability was sufficient for a round of severe thunderstorms to occur.

Multiple trees were snapped. Many tree branches and some trees fell on multiple homes, which inflicted damage. At one point there were 65 trees covering main and secondary roads across the county. All main roads were back open on the afternoon of the 4th, and crews then focused on secondary roads. Many roads were closed as cleanup continued. Emergency management reported 28 residential structures had some form of damage, and a dozen commercial structures were damaged as well. These included farming structures and equipment. One family was displaced from their mobile home because of damage from a fallen tree. A county state of emergency was declared. Peak winds were estimated near 105 mph.

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.

The county was under a severe thunderstorm watch, issued at 06:42 UTC and running to 09:16 UTC.

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 Marginal Risk. The outlook in force was issued at 05:30 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.

The Paducah radar (KPAH), 51 km away, was scanning. The volume nearest the touchdown began at 08:31 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 2021 tornado in KentuckyEvery tornado in Kentucky since 1950Warnings in force in Kentucky nowThe forecast where you are

38 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.