Tornadoes · United States · Iowa · 2017
EF0 tornado, Vinton, Iowa, June 28, 2017
This EF0 tornado ran 0.0 miles across Benton County on June 28, 2017, touching down at 7:26 PM CDT and reaching 10 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.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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 28, 2017
- Touchdown
- 7:26 PM CDT (00:26 UTC)
- Path length
- 0.0 miles (0.0 km)
- Path width
- 10 yards (9 m)
- Deaths
- 0
- Injuries
- 0
- County
- Benton County
- Touchdown point
- 42.154, -91.988
- Lift-off point
- 42.154, -91.988
- Record number
- 1706281826-01
The damage survey
1 damage points were recorded along this path by NWS DVN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 74 mph.
- Brief touchdown captured on video by citizen, which corresponded to damage to two trees adjacent to the corner of a metal outbuilding's roof.
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
Low pressure moving along a cold front helped produce supercell thunderstorms with large hail, damaging winds, and tornadoes over much of Iowa the afternoon and evening of June 28th, 2017. This event produced two EF2 tornadoes between Cedar Rapids and Dubuque, Iowa, and a few other weak tornadoes in eastern Iowa.
A brief touchdown of an EF0 tornado that was seen on a citizen's video was confirmed by a location of isolated damage of two trees and an adjacent corner of a metal outbuilding's roof where a single panel was blown off.
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 tornado watch, issued at 19:55 UTC and running to 03:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 19:55 UTC | 03:00 UTC | Tornado Watch | DVN |
| 00:02 UTC | 00:45 UTC | Severe Thunderstorm Warning | DVN |
| 02:12 UTC | 02:47 UTC | Severe Thunderstorm Warning | DVN |
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 19:58 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.
Davenport, (KDVN), 00:00Z
0.4 hours before the tornado, 137 km from the path. June 29, 2017.
- Mixed-layer CAPE
- 1521 J/kg
- Mixed-layer CIN
- -10 J/kg
- Surface CAPE
- 2161 J/kg
- Mixed-layer LCL
- 1099 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 259 m²/s²
- 0-3 km storm-relative helicity
- 334 m²/s²
- Significant tornado parameter
- 2.7
- Supercell composite
- 15.1
- 0-3 km lapse rate
- 6.8 K/km
Davenport, (KDVN), 12:00Z
11.6 hours after it, 137 km from the path. June 29, 2017.
- Mixed-layer CAPE
- 27 J/kg
- Mixed-layer CIN
- -369 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 968 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 163 m²/s²
- 0-3 km storm-relative helicity
- 175 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.4 K/km
The radar
The Quad Cities radar (KDVN), 131 km away, was scanning. The volume nearest the touchdown began at 00:28 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 23:19 UTC | HAIL 1 | Gladbrook | Tama, IA | |
| 23:45 UTC | TORNADO | 1 Wsw Prairieburg | Linn, IA | LARGE TORNADO WITH DEBRIS. |
| 23:45 UTC | TORNADO | 4 S Central City | Linn, IA | SPOTTER LI158 REPORTED DEBRIS LOFTING |
| 23:48 UTC | TSTM WND DMG | Prairieburg | Linn, IA | HOUSE DOWN FROM TORNADO, PERSON TRAPPED. |
| 23:50 UTC | TSTM WND DMG | Prairieburg | Linn, IA | HOUSES DAMAGED, GRAIN BINS DOWN, AND SEMIS BLOWN OVER FROM TORNADO. |
| 23:55 UTC | TSTM WND DMG | 3 S Buck Creek | Jones, IA | STRUCTURAL DAMAGE, POSSIBLE TORNADO. |
| 00:07 UTC | TSTM WND DMG | 4 W Monticello | Jones, IA | DAMAGE TO BARNS AND OTHER STRUCTURES, POSSIBLE TORNADO. |
| 00:10 UTC | HAIL 1 | La Porte City | Black Hawk, IA | REPORT VIA SOCIAL MEDIA. |
| 00:20 UTC | HAIL 1 | 3 E Vinton | Benton, IA | ALSO 40 TO 50 MPH WIND |
| 00:26 UTC | TORNADO 0 | 2 Se Vinton | Benton, IA | BREIF TOUCHDOWN OF AN EF0 TORNADO SEEN ON CITIZENS VIDEO, CONFIRMED BY LOCATION OF ISOLATED DAMAGE TO TWO TREES AND THE CORNER OF A METAL BUILDING WHERE A ROOFING PANEL WAS BLOWN OFF. |
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 IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are
The other tornadoes of June 28, 2017
25 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| June 28 | 3:46 PM CDT | EF2 | Fremont, IA | 3.7 | 135 | |||
| June 28 | 3:57 PM CDT | EF0 | Adair, IA | 14.9 | 100 | $5,000 | ||
| June 28 | 4:21 PM CDT | EF1 | Page, IA | 2.1 | 75 | |||
| June 28 | 4:21 PM CDT | EF1 | Adams, IA | 3.8 | 100 | $10,000 | ||
| June 28 | 4:25 PM CDT | EF1 | Pierce, WI | 11.3 | 700 | |||
| June 28 | 4:43 PM CDT | EF0 | Adams, IA | 1.9 | 30 | $1,000 | ||
| June 28 | 4:45 PM CDT | EF1 | Adair, IA | 7.6 | 100 | $20,000 | ||
| June 28 | 4:49 PM CDT | EF1 | Burnett, WI | 2.2 | 180 | |||
| June 28 | 5:05 PM CDT | EF2 | Taylor, IA | 7.0 | 1,000 | $75,000 | ||
| June 28 | 5:54 PM CDT | EF1 | Warren, IA | 17.8 | 500 | $85,000 | ||
| June 28 | 6:18 PM CDT | EF0 | Warren, IA | 0.5 | 25 | |||
| June 28 | 6:22 PM CDT | EF0 | Olmsted, MN | 0.0 | 25 | |||
| June 28 | 6:38 PM CDT | EF2 | Linn, IA | 11.7 | 200 | 1 | ||
| June 28 | 6:42 PM CDT | EF0 | Olmsted, MN | 0.4 | 25 | $5,000 | ||
| June 28 | 6:48 PM CDT | EF1 | Gentry, MO | 16.4 | 75 | |||
| June 28 | 6:55 PM CDT | EF1 | Green, WI | 2.2 | 300 | $325,000 | ||
| June 28 | 6:55 PM CDT | EF1 | Green, WI | 0.6 | 150 | $145,000 | ||
| June 28 | 7:07 PM CDT | EF0 | Olmsted, MN | 0.5 | 25 | $3,000 | ||
| June 28 | 7:14 PM CDT | EF2 | Jones, IA | 2.5 | 30 | |||
| June 28 | 7:38 PM CDT | EF0 | Rock, WI | 0.8 | 100 | $60,000 | ||
| June 28 | 7:56 PM CDT | EF1 | Jones, IA | 2.0 | 15 | |||
| June 28 | 8:14 PM CDT | EF1 | Boone, IL | 5.9 | 200 | |||
| June 28 | 8:23 PM CDT | EF1 | Winnebago, IL | 1.6 | 100 | |||
| June 28 | 8:31 PM CDT | EF0 | Nodaway, MO | 1.3 | 25 | |||
| June 28 | 8:50 PM CDT | EF0 | Gentry, MO | 1.4 | 25 |
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.