Tornadoes · United States · Iowa · 2015
EF0 tornado, Meroa, Iowa, July 16, 2015
This EF0 tornado ran 2.1 miles across Mitchell County on July 16, 2015, touching down at 8:34 PM CDT and reaching 40 yards wide. It killed nobody, and did $40,000 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.
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
- July 16, 2015
- Touchdown
- 8:34 PM CDT (01:34 UTC)
- Lifted
- 8:36 PM CDT (01:36 UTC)
- On the ground
- 2 minutes
- Path length
- 2.1 miles (3.3 km)
- Path width
- 40 yards (37 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $40,000
- Crop damage
- $10,000
- County
- Mitchell County
- Touchdown point
- 43.258, -92.941
- Lift-off point
- 43.272, -92.905
- Record number
- 1507161934-01
The damage survey
1 damage points were recorded along this path by NWS ARX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 83 mph.
- Garage flipped with 5-6 trees uprooted.
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
A small tornado touched down during the evening of July 16th southwest of Osage (Mitchell County). The tornado damaged three farms along its path where it flipped and damaged a garage, destroyed a barn and damaged house siding from flying debris. In addition, several trees and powerlines were downed and crops were damaged.
A tornado briefly touched down southwest of Osage. A garage was flipped, a barn destroyed and house siding damaged by flying debris. Multiple trees were either uprooted or snapped off and powerlines were downed.
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.
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 General Thunderstorms Risk. The outlook in force was issued at 00:49 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.
Minneapolis, MN (KMPX), 00:00Z
1.6 hours before the tornado, 184 km from the path. July 17, 2015.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -373 J/kg
- Surface CAPE
- 5 J/kg
- Mixed-layer LCL
- 596 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 106 m²/s²
- 0-3 km storm-relative helicity
- 112 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.0 K/km
Minneapolis, MN (KMPX), 12:00Z
10.4 hours after it, 184 km from the path. July 17, 2015.
- Mixed-layer CAPE
- 893 J/kg
- Mixed-layer CIN
- -117 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 857 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 113 m²/s²
- 0-3 km storm-relative helicity
- 143 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
- 0-3 km lapse rate
- 3.7 K/km
The radar
The La Crosse radar (KARX), 153 km away, was scanning. The volume nearest the touchdown began at 01:34 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 |
|---|---|---|---|---|
| 01:34 UTC | TORNADO | 6 Sw Osage | Mitchell, IA | BRIEF TORNADO TOUCHED DOWN SOUTHWEST OF OSAGE FLIPPING A GARAGE...DESTROYING A BARN AND CAUSING DAMAGE TO SIDING DUE TO FLYING DEBRIS. MULTIPLE TREES WERE UPROOTED OR SNAPPED AND POWER LINES DOWNED. TORNADO LASTED APPROX |
| 02:21 UTC | LIGHTNING | 4 Se New Haven | Mitchell, IA | MACHINE SHED CAUGHT ON FIRE FROM LIGHTNING STRIKE |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2015 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are
The other tornadoes of July 16, 2015
8 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| July 16 | 5:14 PM CDT | EF0 | Henry, IA | 1.5 | 10 | |||
| July 16 | 6:09 PM CDT | EF1 | Henderson, IL | 0.8 | 100 | $25,000 | ||
| July 16 | 6:49 PM CDT | EF1 | Warren, IL | 1.4 | 50 | $2,000 | ||
| July 16 | 7:00 PM CDT | EF1 | Rock Island, IL | 1.1 | 200 | $2,000 | ||
| July 16 | 7:09 PM CDT | EF2 | Warren, IL | 1.7 | 300 | $150,000 | ||
| July 16 | 7:13 PM CDT | EF2 | Warren, IL | 6.0 | 700 | 1 | $1.5 million | |
| July 16 | 8:48 PM CDT | EF0 | Whiteside, IL | 0.6 | 10 | |||
| July 16 | 11:39 PM CDT | EF2 | Tazewell, IL | 2.4 | 250 | 1 | $1.2 million |
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.