Tornadoes · United States · North Carolina · 2021

EF0 tornado, St Johns, North Carolina, June 20, 2021

This EF0 tornado ran 3.0 miles across Chowan County on June 20, 2021, touching down at 3:07 PM EDT and reaching 75 yards wide. It killed nobody, and did $25,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  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.

The record

Rating
EF0
Date
June 20, 2021
Touchdown
3:07 PM EDT (19:07 UTC)
Lifted
3:13 PM EDT (19:13 UTC)
On the ground
6 minutes
Path length
3.0 miles (4.8 km)
Path width
75 yards (69 m)
Deaths
0
Injuries
0
Property damage
$25,000
County
Chowan County
Touchdown point
36.040, -76.488
Lift-off point
36.071, -76.432
Record number
2106201307-01

What the Weather Service recorded

Isolated severe thunderstorm associated with a surface trough produced a weak tornado across portions of northeast North Carolina.

A tornado touched down near Somerset in Chowan county. The main damage was to trees that snapped off and large limbs that came down to block roadways. Tree damage was discovered beginning near the intersection of Indian Trail Road and Sycamore Road. The tornado continued to move eastward with more tree damage occurring along portions of Drummond Point Road before lifting after damaging more trees along Lloyd Overton Lane. No structures were damaged from the tornado, except for a metal building that had a tree fall on it.

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

The warnings

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.

Issued (UTC)ExpiredProductOffice
19:10 UTC19:23 UTCTornado WarningAKQ

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 forecast that day

The Storm Prediction Center had this point in a Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:22 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 air that afternoon

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.

Newport, NC (KMHX), 12:00Z

7.1 hours before the tornado, 147 km from the path. June 20, 2021.

Skew-T log-pSkew-T log-p diagram, Newport, NC at 12:00Z on 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 215 joules per kilogram, CIN -48, lifted condensation level 986 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Newport, NC at 12:00Z on 2021-06-20The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 115 square meters per square second, 0 to 6 km bulk shear 36 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
215 J/kg
Mixed-layer CIN
-48 J/kg
Surface CAPE
83 J/kg
Mixed-layer LCL
986 m above ground
0-6 km bulk shear
36 kt
0-1 km bulk shear
27 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

Newport, NC (KMHX), 00:00Z

4.9 hours after it, 147 km from the path. June 21, 2021.

Skew-T log-pSkew-T log-p diagram, Newport, NC at 00:00Z on 2021-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 502 joules per kilogram, CIN -52, lifted condensation level 931 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Newport, NC at 00:00Z on 2021-06-21The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 116 square meters per square second, 0 to 6 km bulk shear 23 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
502 J/kg
Mixed-layer CIN
-52 J/kg
Surface CAPE
1525 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
23 kt
0-1 km bulk shear
31 kt
0-1 km storm-relative helicity
116 m²/s²
0-3 km storm-relative helicity
154 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3
0-3 km lapse rate
5.6 K/km

Open this sounding in Storm Lab

The radar

The Norfolk radar (KAKQ), 114 km away, was scanning. The volume nearest the touchdown began at 19:09 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.

What was reported nearby

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

Time (UTC)ReportWhereCountyRemark
19:11 UTCTORNADO1 Ene SomersetChowan, NCCHOWAN COUNTY EMERGENCY MANAGER PROVIDED PICTURES AND DAMAGE PATH INFORMATION IN THE SOMERSET AREA OF CHOWAN COUNTY. THE DAMAGE WAS CONSISTENT WITH AN EF0. THE PATH WAS ROUGHLY 2.5 MILES AND THE TORNADO WAS ON THE GROUND

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

This ground now

The live radar over the trackEvery 2021 tornado in North CarolinaEvery tornado in North Carolina since 1950Warnings in force in North Carolina nowThe forecast where you are

The other tornadoes of June 20, 2021

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 206:40 PM CDTEF1Marion, IA1.5150$10,000
June 208:06 PM CDTEF1Dubuque, IA3.430
June 209:23 PM EDTEF1Lenawee, MI2.7125$250,000
June 2010:54 PM CDTEF0DuPage, IL0.475
June 2011:02 PM CDTEF3Naperville–Woodridge tornado, IL17.660011
June 2011:08 PM CDTEF0Will, IL4.8200
June 2012:11 AM CDTEF0Porter, IN3.3150

What this means

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.

Sources

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