Tornadoes · United States · Indiana · 2020

EF0 tornado, Ade, Indiana, August 10, 2020

This EF0 tornado ran 0.9 miles across Newton County on August 10, 2020, touching down at 4:15 PM CDT and reaching 40 yards wide. It killed nobody.

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
August 10, 2020
Touchdown
4:15 PM CDT (21:15 UTC)
Lifted
4:16 PM CDT (21:16 UTC)
On the ground
1 minutes
Path length
0.9 miles (1.4 km)
Path width
40 yards (37 m)
Deaths
0
Injuries
0
County
Newton County
Touchdown point
40.851, -87.442
Lift-off point
40.850, -87.426
Record number
2008101515-01

The damage survey

6 damage points were recorded along this path by NWS LOT, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 70 mph.

  • From Ray Chambers Newton County EMA survey.
  • Metal farm building had portion of roof peeled off. From Ray Chambers Newton County EMA survey.
  • Large TV antenna knocked down. From Ray Chambers Newton County EMA survey.
  • Convergent rotation pattern in corn from drone picture. From Ray Chambers Newton County EMA survey.

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

What the Weather Service recorded

During the late morning through the afternoon of Monday August 10th, a line of intense thunderstorms known as a derecho brought widespread severe wind damage across Iowa, northern Illinois and northern Indiana.||In northwest Indiana alone, the winds downed hundreds of trees, as well as caused damage to homes, businesses and infrastructure. There were two injuries reported in northwest Indiana within the NWS Chicago/Romeoville County Warning Area (CWA) due to falling trees. It was estimated that over 200,000 customers lost power at the height of the derecho across all of northern Indiana. While much of the damage was due to straight line winds, there was also one tornado documented in northwest Indiana.||The combination of high moisture, explosive instability and very strong atmospheric wind flow for mid-summer had developed quickly over the Corn Belt region on the morning of August 10th. This resulted in a progressive, well-organized complex of storms for hundreds of miles and at times traveling nearly 70 mph. After bringing extensive damage from extreme wind speeds in Iowa that morning, the damage transitioned across northern Illinois from widespread wind damage to narrow, brief and intense swaths associated with compact circulations within the thunderstorm line, some of which were associated with tornadoes.

A brief tornado with peak winds of 70 mph touched down southwest of Brook. The tornado made a path through corn fields, indicating a convergent pattern. The only damage was to metal farm buildings west of Route 41 and south of W 1000 S Road. One had a portion of its metal roof peeled off and doors were blown out of another. The path of this tornado was determined, in part, using high resolution satellite imagery.

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.

The county was under a severe thunderstorm watch, issued at 16:28 UTC and running to 22:23 UTC.

Issued (UTC)ExpiredProductOffice
16:28 UTC22:23 UTCSevere Thunderstorm WatchLOT
20:31 UTC22:00 UTCSevere Thunderstorm WarningLOT

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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:38 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.

Lincoln, IL (KILX), 12:00Z

9.3 hours before the tornado, 126 km from the path. August 10, 2020.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 12:00Z on 2020-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1597 joules per kilogram, CIN -128, lifted condensation level 1046 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, Lincoln, IL at 12:00Z on 2020-08-10The 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 167 square meters per square second, 0 to 6 km bulk shear 21 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
1597 J/kg
Mixed-layer CIN
-128 J/kg
Surface CAPE
962 J/kg
Mixed-layer LCL
1046 m above ground
0-6 km bulk shear
21 kt
0-1 km bulk shear
22 kt
0-1 km storm-relative helicity
167 m²/s²
0-3 km storm-relative helicity
241 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6
0-3 km lapse rate
3.8 K/km

Open this sounding in Storm Lab

Lincoln, IL (KILX), 00:00Z

2.7 hours after it, 126 km from the path. August 11, 2020.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2020-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -75157, lifted condensation level 1523 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Lincoln, IL at 00:00Z on 2020-08-11The 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 -307 square meters per square second, 0 to 6 km bulk shear 33 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
0 J/kg
Mixed-layer CIN
-75157 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1523 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
34 kt
0-1 km storm-relative helicity
-307 m²/s²
0-3 km storm-relative helicity
-226 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.2 K/km

Open this sounding in Storm Lab

The radar

The Chicago radar (KLOT), 100 km away, was scanning. The volume nearest the touchdown began at 21:16 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
21:15 UTCTSTM WND DMG1 Wsw Cedar LakeLake, IN6 INCH DIAMETER TREE DOWNED NEAR PARRISH AVENUE AND 141ST AVENUE IN CEDAR LAKE. TIME ESTIMATED BY RADAR.
21:15 UTCTORNADO4 Wsw BrookNewton, INTHIS EF-0 TORNADO WAS ON THE GROUND FOR LESS THAN 1 MINUTE AND PRODUCED MINOR DAMAGE TO A METAL FARM BUILDING IMMEDIATELY WEST OF STATE HIGHWAY 41.
21:20 UTCTSTM WND DMG4 W BrookNewton, INPOWERLINES DOWN ACROSS US-41 NEAR IN-16 BETWEEN MOROCCO AND KENTLAND. TIME ESTIMATED BY RADAR.
21:21 UTCTSTM WND DMG4 N KentlandNewton, IN30 BY 50 FOOT CORN FIELD FLATTENED WITH SWILING DENOTED IN CORNFALL. ALSO, METAL SHEDS DAMAGED WITH PARTS OF ROOFS AND DOORS MISSING. NO MAJOR STRUCTURE DAMAGE WAS NOTED TO FARM HOUSES IN THE AREA. POSSIBLE TORNADO. TIME
21:21 UTCTSTM WND DMGMoroccoNewton, INBRICK CHIMNEY BLOWN DOWN; MULTIPLE TREE LIMBS BLOWN DOWN. TIME ESTIMATED BY RADAR.
22:05 UTCTSTM WND DMG3 Wnw SitkaWhite, INTREE DOWNED ACROSS LOWES ROAD BRIDGE AND BLOCKING TRAFFIC, APPROXIMATELY 1 FT IN DIAMETER. DELAYED REPORT.
22:08 UTCTSTM WND DMGSitkaWhite, INPOWER LINE DOWNED AT 500N AND 700E. DELAYED REPORT.
22:10 UTCTSTM WND DMG1 Ssw SitkaWhite, IN1-2 FT DIAMETER TREE DOWNED BLOCKING THE ROAD ON E 400 N NEAR RACCOON CIRCLE. DELAYED REPORT.

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

This ground now

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

The other tornadoes of August 10, 2020

26 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 1011:30 AM CDTUnratedMarshall, IA1.050
August 1011:36 AM CDTUnratedMarshall, IA0.450
August 1011:39 AM CDTEF1Marshall, IA2.9100$20,000
August 1012:01 PM CDTUnratedTama, IA1.540
August 1012:31 PM CDTUnratedLinn, IA0.940
August 1012:32 PM CDTEF0Grant, WI0.650$15,000
August 102:12 PM CDTEF0Stephenson, IL4.650
August 102:37 PM CDTEF0Winnebago, IL1.650
August 102:47 PM CDTEF1Winnebago, IL9.2300
August 102:50 PM CDTEF0DeKalb, IL6.340
August 102:59 PM CDTEF1LaSalle, IL0.9150
August 103:05 PM CDTEF1McHenry, IL5.7200
August 103:12 PM CDTEF1Kane, IL1.240
August 103:15 PM CDTEF1Kendall, IL14.4250
August 103:35 PM CDTEF1DuPage, IL0.4100
August 103:38 PM CDTEF0Walworth, WI3.350$12,000
August 103:39 PM CDTEF1DuPage, IL2.1200
August 103:41 PM CDTEF1Lake, IL to WI6.3150$250,000
August 103:54 PM CDTEF1Cook, IL4.8300
August 103:57 PM CDTEF0Cook, IL2.0350
August 103:59 PM CDTEF1Cook, IL3.2300
August 104:04 PM CDTEF0Kankakee, IL1.5150
August 105:05 PM EDTEF1Washington, NY1.5100$75,000
August 106:32 PM EDTEF1Saint Joseph, IN2.4100
August 106:55 PM EDTEF1Kosciusko, IN3.1100
August 107:43 PM EDTEF0Kosciusko, IN0.250

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.