Tornadoes · United States · Ohio · 2017

EF0 tornado, Chattanooga to Rockford, Ohio, July 10, 2017

From Chattanooga to Rockford, this EF0 tornado ran 6.3 miles across Mercer County on July 10, 2017, touching down at 8:14 PM EDT and reaching 150 yards wide. It killed nobody, and did $10,000 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
July 10, 2017
Touchdown
8:14 PM EDT (00:14 UTC)
Lifted
8:31 PM EDT (00:31 UTC)
On the ground
17 minutes
Path length
6.3 miles (10.2 km)
Path width
150 yards (137 m)
Deaths
0
Injuries
0
Property damage
$10,000
County
Mercer County
Touchdown point
40.713, -84.795
Lift-off point
40.697, -84.675
Record number
1707101814-01

What the Weather Service recorded

A series of upper level disturbances moving across the region brought several rounds of severe storms through the day.

The tornado touched down near Winkler Road just west of State Route 49. As the tornado moved east, damage was observed at a residence on the southwest corner of Winkler Road and Short Road. The tornado damaged the roof of a home and several nearby trees were also damaged.||As the tornado continued east, it caused damage to the roof of a house west of Wabash Road, along with damage to trees on the property.||The tornado moved east-southeast across Hill Road, crossing Winkler Road and damaging crops and trees along its path. Rotational scarring was noted in the corn fields adjacent to Winkler Road and Jordan Road.||The tornado crossed Jordan Road, moving east-southeast to near the intersection of Lee Road and Erastus-Durbin Road. At a property on the southeast corner of this intersection, one outbuilding was destroyed, with its debris scattered into the field to the east.||The tornado damaged another area of trees along Township Line Road and then continued east-southeast into open fields north of Rockford West Road before it dissipated.

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
00:12 UTC01:00 UTCSevere Thunderstorm WarningILN
00:26 UTC01:00 UTCTornado WarningILN
00:58 UTC01:13 UTCSevere Thunderstorm WarningILN
02:19 UTC02:54 UTCSevere Thunderstorm WarningILN
03:13 UTC05:15 UTCFlood AdvisoryILN
07:30 UTC22:23 UTCFlash Flood WatchILN

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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:54 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

0.2 hours before the tornado, 163 km from the path. July 11, 2017.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 00:00Z on 2017-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 299 joules per kilogram, CIN -35, lifted condensation level 1494 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 2017-07-11The 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 73 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
299 J/kg
Mixed-layer CIN
-35 J/kg
Surface CAPE
1455 J/kg
Mixed-layer LCL
1494 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
12 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
192 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6
0-3 km lapse rate
7.0 K/km

Open this sounding in Storm Lab

Cncnati-Daytn, OH (KILN), 12:00Z

11.8 hours after it, 163 km from the path. July 11, 2017.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 12:00Z on 2017-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1049 joules per kilogram, CIN -100, lifted condensation level 979 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 12:00Z on 2017-07-11The 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 127 square meters per square second, 0 to 6 km bulk shear 22 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
1049 J/kg
Mixed-layer CIN
-100 J/kg
Surface CAPE
1146 J/kg
Mixed-layer LCL
979 m above ground
0-6 km bulk shear
22 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.8
0-3 km lapse rate
5.2 K/km

Open this sounding in Storm Lab

The surface observations

Wapakoneta (AXV), 44 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:31 UTC80.666.2230° 10 kt1012.5
22:51 UTC80.664.4230° 8 kt1012.5
23:12 UTC80.664.4220° 6 kt1012.5
23:31 UTC80.664.4220° 5 kt1012.5
23:51 UTC78.868230° 4 kt1012.5
00:12 UTC78.868200° 5 kt1012.2
00:31 UTC78.868190° 6 kt1011.9
00:51 UTC78.868190° 7 kt1012.2
01:11 UTC78.866.2180° 7 kt1011.9VCTS
01:31 UTC78.866.2180° 11 kt1011.9TS
01:52 UTC78.864.4190° 10 kt161012.2TS
02:11 UTC78.864.4190° 9 kt1012.2VCTS

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

The radar

The Northern Indiana radar (KIWX), 109 km away, was scanning. The volume nearest the touchdown began at 00:14 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
00:20 UTCTORNADO 05 Wnw RockfordMercer, OHA TORNADO NORTHWEST OF ROCKFORD DAMAGED CROPS, TREES, AND ONE OUTBUILDING.
00:33 UTCFUNNEL CLOUD2 W RockfordMercer, OHFUNNEL CLOUD REPORTED WEST SIDE OF ROCKFORD.
02:12 UTCFLOODJonestownVan Wert, OHREPORTED 5.22 OF RAIN. SEVERAL VEHICLES STRANDED IN HIGH WATER.
02:12 UTCLIGHTNINGJonestownVan Wert, OHREPORT OF A HOUSE FIRE DUE TO LIGHTNING.
02:12 UTCHEAVY RAIN 5.22JonestownVan Wert, OHSTORM TOTAL.
02:31 UTCHAIL 2.5MendonMercer, OH
02:45 UTCHAIL 1SpencervilleAllen, OHDELAYED REPORT. HAIL IMAGES RELAYED VIA LIMA MEDIA. PICTURES LOOK SLIGHTLY LARGER THAN QUARTER SIZED.

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

This ground now

The live radar over the trackEvery 2017 tornado in OhioEvery tornado in Ohio since 1950Warnings in force in Ohio nowThe forecast where you are

The other tornadoes of July 10, 2017

6 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 1012:00 PM MDTUnratedGarfield, UT0.11
July 103:57 PM EDTEF0Beaver, PA3.275$30,000
July 105:45 PM CDTEF0Peoria, IL1.650
July 107:35 PM EDTEF0Meigs, OH0.450$15,000
July 107:53 PM EDTEF1Cass, IN3.8200
July 107:58 PM EDTEF1Miami, IN3.0100

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.