EF1 tornado, Rion to Winnsboro Arpt, South Carolina, 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

4:23 PM EDT (20:23 UTC)

Lifted

4:29 PM EDT (20:29 UTC)

On the ground

6 minutes

Path length

3.9 miles (6.3 km)

Path width

300 yards (274 m)

Deaths

0

Injuries

0

County

Fairfield County

Touchdown point

34.303, -81.141

Lift-off point

34.314, -81.077

Record number

2105041423-01

37 damage points were recorded along this path by NWS CAE, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 105 mph.

• External wall of hangar pulled outward from structure.
• Numerous hardwood trees snapped across this property. Damage was most intense near the pond.
• Multiple softwood trees snapped and uprooted across this property.
• Multiple hardwood trees snapped and large branches down near the intersection of Garibaldi and Rion Rd. This resulted in a tree falling on a power line.

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

Sufficient atmospheric instability and shear, along with interaction between surface boundaries, provided scattered severe thunderstorms, producing wind damage, along with a tornado.

A National Weather Service storm survey team confirmed an EF1 tornado, with peak|winds of 105 mph, near Rion in Fairfield County, SC. The tornado began near Hard|Rock Rd, uprooting and snapping numerous trees as it moved northeast across Ridge|Rd and Granite Ln. The tornado then intensified to EF1 strength as it crossed Rion Rd|and Stony Cir, snapping and uprooting many large hardwood trees and causing minor|damage to siding on a couple of homes. ||The tornado then continued its track east across the Fairfield County Airport where|damage occurred to a total of five planes and one hangar. One plane was totaled|after the tornado removed it from its tie-down ropes and flipped it. The plane was|tossed 100 yards into a field between runways and one of its wings was removed.|The tie-down ropes were still in place when the survey occurred with pieces from the|plane still attached. Security camera video at the airport documented this event. The|hangar that was damaged had a portion of two external walls pushed outward by|the tornado. ||The tornado then continued east across State Highway 269, Old Ruff Rd, US Highway 321 South and Oxner Rd and Roddy Rd, mainly producing EF0 damage with trees|uprooted and snapped. One large tree fell on a home on US Highway 321 South,|causing substantial roof damage.| |The tornado then dissipated near Little Cedar Creek.

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.

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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:49 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.

Winnsboro (FDW), 1 km from the path, in the two hours either side.

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

The Columbia radar (KCAE), 40 km away, was scanning. The volume nearest the touchdown began at 20:21 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 South CarolinaEvery tornado in South Carolina since 1950Warnings in force in South Carolina 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.