Tornadoes · United States · Indiana · 2021

EF1 tornado, Chesterville, Indiana, June 18, 2021

This EF1 tornado ran 0.5 miles across Dearborn County on June 18, 2021, touching down at 9:01 PM EDT and reaching 150 yards wide. It killed nobody, and did $50,000 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 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.

The record

Rating
EF1
Date
June 18, 2021
Touchdown
9:01 PM EDT (01:01 UTC)
Lifted
9:02 PM EDT (01:02 UTC)
On the ground
1 minutes
Path length
0.5 miles (0.8 km)
Path width
150 yards (137 m)
Deaths
0
Injuries
0
Property damage
$50,000
County
Dearborn County
Touchdown point
39.059, -85.053
Lift-off point
39.056, -85.045
Record number
2106181901-01

What the Weather Service recorded

Thunderstorms developed during the afternoon and evening hours as a low pressure system moved through a warm and humid airmass that was in place across the Ohio Valley.

The tornado likely began in a wooded area behind Longbranch Road, where downed trees were first noted. The most significant damage occurred at two residences on Longbranch Road. Nearly half of the metal roof of one residence was lifted and thrown in multiple directions, with insulation splattered on the residence and even onto parked vehicles. Trees on both properties were knocked down or blown over in multiple directions and the tree damage exhibited a very convergent pattern. The tornado is believed to have lifted in another wooded area to the southeast of Longbranch Road, as no other damage was seen on any roads to the southeast.

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.

The county was under a tornado watch, issued at 00:09 UTC and running to 02:48 UTC.

Issued (UTC)ExpiredProductOffice
22:00 UTC15:28 UTCFlash Flood WatchILN
00:09 UTC02:48 UTCTornado WatchILN
00:10 UTC01:00 UTCSevere Thunderstorm WarningILN
00:44 UTC01:30 UTCSevere Thunderstorm WarningILN
00:56 UTC01:30 UTCSevere Thunderstorm WarningILN
01:00 UTC04:00 UTCFlash Flood WarningILN
01:02 UTC01:30 UTCTornado WarningILN
01:11 UTC01:45 UTCTornado WarningILN
01:39 UTC04:45 UTCFlood AdvisoryILN
02:48 UTC07:00 UTCSevere Thunderstorm WatchILN
07:44 UTC10:45 UTCFlood AdvisoryILN
10:39 UTC10:58 UTCFlood AdvisoryILN
10:54 UTC00:00 UTCFlash Flood WarningILN
17:18 UTC02:03 UTCFlood AdvisoryILN

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 Enhanced Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:48 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.

Cncnati-Daytn, OH (KILN), 00:00Z

1.0 hours before the tornado, 115 km from the path. June 19, 2021.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 00:00Z on 2021-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2257 joules per kilogram, CIN -56, lifted condensation level 1236 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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, Cncnati-Daytn, OH at 00:00Z on 2021-06-19The 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 214 square meters per square second, 0 to 6 km bulk shear 34 knots.19395878Sfc1 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
2257 J/kg
Mixed-layer CIN
-56 J/kg
Surface CAPE
3692 J/kg
Mixed-layer LCL
1236 m above ground
0-6 km bulk shear
34 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
214 m²/s²
0-3 km storm-relative helicity
240 m²/s²
Significant tornado parameter
1.9
Supercell composite
17.6
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The surface observations

Harrison (I67), 33 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
23:15 UTC87.869.8210° 11 kt1009.5
23:35 UTC8669.8210° 11 kt191009.5
23:55 UTC8669.8210° 9 kt151009.1
00:15 UTC84.269.8210° 10 kt161009.5
00:35 UTC84.269.8220° 8 kt181009.8
00:55 UTC7769.8290° 11 kt181011.2
01:15 UTC6864.4300° 14 kt251014.2
01:35 UTC6862.6190° 8 kt1012.9
01:55 UTC6862.6140° 8 kt1011.5
02:15 UTC6862.6210° 3 kt1012.9
02:35 UTC6862.6220° 3 kt1013.2
02:55 UTC6862.6170° 3 kt1013.9

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

The radar

The Cincinnati radar (KILN), 113 km away, was scanning. The volume nearest the touchdown began at 00:59 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
00:44 UTCTSTM WND DMG1 E NewpointDecatur, INROOF OFF A BUILDING.
00:45 UTCTSTM WND DMG5 Se SunmanDearborn, INTREES AND POWER LINES WERE BLOWN DOWN ACROSS THE COUNTY. A HOUSE WAS STRUCK BY LIGHTNING AT HIDDEN VALLEY LAKE.
00:47 UTCTSTM WND DMG4 Ne OsgoodRipley, INTREE REPORTED INTO A HOUSE. NO INJURIES. TIME ESTIMATED FROM RADAR.
00:47 UTCTSTM WND GST 58BatesvilleRipley, IN
00:47 UTCTSTM WND DMG4 Sw ClarksburgDecatur, INTREES DOWN ACROSS NORTHEASTERN DECATUR COUNTY.
00:51 UTCTORNADO 15 Nw MilanRipley, INNWS STORM SURVEY CONFIRMS AN EF-1 TORNADO WITH A PATH LENGTH OF 6.2 MILES.
00:55 UTCTSTM WND DMGMilanRipley, INROOF REPORTED OFF A HOME. A TREE KNOCKED DOWN INTO A HOUSE. BARN DAMAGE REPORTED. TIME ESTIMATED FROM RADAR.
00:56 UTCTSTM WND DMGVersaillesRipley, INMANY DOWNED TREES AND POWER LINES ACROSS ROADWAYS COUNTY WIDE. TIME ESTIMED FROM RADAR FOR VERSAILLES.
00:58 UTCTSTM WND DMG2 Nw MilanRipley, INEXTENSIVE AND CONSIDERABLE TREE DAMAGE AT MULTIPLE PROPERTIES NEAR THE INTERSECTION OF EAST COUNTY RD. 475 N AND NORTH COUNTY RD 850 E. TIME ESTIMATED BY RADAR.
01:01 UTCTORNADO 13 N DillsboroDearborn, INNWS STORM SURVEY CONFIRMS AN EF-1 TORNADO WITH A PATH LENGTH OF ONE-HALF MILE.
01:12 UTCTSTM WND GST 59LawrenceburgDearborn, IN
01:15 UTCTSTM WND DMG5 Sse BrightDearborn, INPUBLIC REPORT OF ROOF DAMAGE TO A BUISNESS IN HIDDEN VALLEY, IN.
02:51 UTCTSTM WND DMG1 Sse DeputyJefferson, INDELAYED REPORT...TWITTER POST ABOUT LOTS OF DEBRIS AND TREES DOWN ON BLAKE ROAD SOUTH OF DEPUTY. TIME ESTIMATED FROM RADAR.

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 IndianaEvery tornado in Indiana since 1950Warnings in force in Indiana nowThe forecast where you are

The other tornadoes of June 18, 2021

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 1811:50 AM CDTEF1Knox, IL10.3250$150,000
June 183:50 PM EDTEF2Jay, IN5.4500
June 184:12 PM EDTEF2Mercer, OH5.6200$1.0 million
June 188:38 PM EDTEF1Montgomery, OH2.8100$60,000
June 188:51 PM EDTEF1Ripley, IN6.2150$100,000
June 189:09 PM EDTEF1Boone, KY2.8175$50,000
June 1812:37 AM CDTEF0Harrison, MS0.550$50,000

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.