Tornadoes · United States · Ohio · 2012
EF0 tornado, Lebanon Warren Co Ar to Genntown, Ohio, May 1, 2012
From Lebanon Warren Co Ar to Genntown, this EF0 tornado ran 0.0 miles across Warren County on May 1, 2012, touching down at 6:24 PM EDT and reaching 50 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.
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
- May 1, 2012
- Touchdown
- 6:24 PM EDT (22:24 UTC)
- Lifted
- 6:25 PM EDT (22:25 UTC)
- On the ground
- 1 minutes
- Path length
- 0.0 miles (0.0 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $10,000
- County
- Warren County
- Touchdown point
- 39.470, -84.190
- Lift-off point
- 39.470, -84.189
- Record number
- 1205011624-01
What the Weather Service recorded
A warm front lifting across the Ohio Valley during the morning brought into the area a very unstable airmass. Numerous thunderstorms developed during the afternoon and evening. The environment was favorable for large hail and damaging winds. However, a few boundaries helped to produce localized favorable conditions for tornadoes. In addition, some storms occurred repeatedly over the same areas, causing an increased risk for flash flooding and flooding to occur.
The brief tornado touched down and caused damage to one structure, auto damage, and damage to outdoor furniture. Based on the damage surveyed, the maximum estimated wind speed of this tornado was 80 miles per hour.
The tornado touched down and uprooted or snapped about 10 to 15 trees. Minor structural damage also occurred. Based on the damage surveyed, the maximum estimated wind speed of this tornado was 80 miles per hour.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
12 minutes of warning. NWS ILN issued a tornado warning for this county at 22:12 UTC, 12 minutes before the tornado touched down, in force until 22:45 UTC.
The county was under a tornado watch, issued at 19:05 UTC and running to 22:40 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 19:05 UTC | 22:40 UTC | Tornado Watch | ILN |
| 21:52 UTC | 22:30 UTC | Severe Thunderstorm Warning | ILN |
| 22:12 UTC | 22:45 UTC | Tornado Warning | ILN |
| 22:12 UTC | 02:15 UTC | Flood Advisory | ILN |
| 22:34 UTC | 23:00 UTC | Tornado Warning | ILN |
| 22:40 UTC | 02:45 UTC | Tornado Watch | ILN |
| 02:30 UTC | 05:30 UTC | Flood Advisory | ILN |
| 03:29 UTC | 03:48 UTC | Severe Thunderstorm Warning | ILN |
| 04:12 UTC | 08:15 UTC | Flash Flood Warning | ILN |
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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:52 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), 12:00Z
10.4 hours before the tornado, 34 km from the path. May 1, 2012.
- Mixed-layer CAPE
- 15 J/kg
- Mixed-layer CIN
- -1 J/kg
- Surface CAPE
- 60 J/kg
- Mixed-layer LCL
- 516 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 47 m²/s²
- 0-3 km storm-relative helicity
- 93 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.9 K/km
The surface observations
Dayton (MGY), 14 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 20:53 UTC | 73 | 64 | 110° 6 kt | 1014.2 | ||
| 21:46 UTC | 71.6 | 64.4 | 80° 4 kt | 1013.9 | VCTS | |
| 21:53 UTC | 71 | 64 | 80° 3 kt | 1014.2 | VCTS | |
| 22:10 UTC | 69.8 | 64.4 | 30° 5 kt | 1014.2 | VCTS +RA BR | |
| 22:24 UTC | 68 | 66.2 | 150° 12 kt | 1014.6 | +TSRA BR | |
| 22:31 UTC | 66.2 | 64.4 | 170° 16 kt | 23 | 1014.9 | +TSRA BR |
| 22:35 UTC | 66.2 | 62.6 | 150° 9 kt | 23 | 1014.2 | -TSRA BR |
| 22:53 UTC | 67 | 62 | 190° 11 kt | 1014.6 | VCTS | |
| 23:06 UTC | 66.2 | 62.6 | 170° 7 kt | 1014.6 | VCTS | |
| 23:38 UTC | 66.2 | 62.6 | 3 kt | 1014.6 | -RA | |
| 23:49 UTC | 66.2 | 62.6 | 250° 4 kt | 1014.9 | VCTS -RA BR | |
| 23:53 UTC | 66 | 62 | 250° 4 kt | 1014.9 | VCTS RA BR |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Cincinnati radar (KILN), 32 km away, was scanning. The volume nearest the touchdown began at 22:24 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 |
|---|---|---|---|---|
| 21:27 UTC | HAIL 1.75 | Cincinnati | Hamilton, OH | |
| 21:29 UTC | HAIL 1.75 | White Oak | Hamilton, OH | |
| 21:30 UTC | HAIL 1 | White Oak | Hamilton, OH | |
| 21:32 UTC | HAIL 1 | Dent | Hamilton, OH | |
| 21:33 UTC | TSTM WND GST 55 | Oxford | Butler, OH | |
| 21:39 UTC | HAIL 1 | Wyoming | Hamilton, OH | |
| 21:55 UTC | HAIL 1.75 | Deer Park | Hamilton, OH | |
| 22:03 UTC | FUNNEL CLOUD | Trenton | Butler, OH | |
| 22:05 UTC | FLOOD | Wyoming | Hamilton, OH | 1 FOOT OF WATER FLOWING OVER ROAD |
| 22:06 UTC | HAIL 1 | New Market | Highland, OH | HAIL DAMAGE TO CARS. |
| 22:15 UTC | TSTM WND GST 50 | 1 E Middletown | Butler, OH | |
| 22:18 UTC | HAIL 0.88 | 2 W Wilmington | Clinton, OH | |
| 22:20 UTC | HAIL 0.75 | 4 W Wilmington | Clinton, OH | |
| 22:20 UTC | TORNADO 0 | 1 Nw Lebanon | Warren, OH | NWS STORM SURVEY CONFIRMS BRIEF EF0 TORNADO WITH MINOR DAMAGE TO A STRUCTURE AND AUTOMOBILE |
| 22:24 UTC | FLOOD | Cincinnati | Hamilton, OH | HIGH WATER ACROSS THE COUNTY |
| 22:24 UTC | HAIL 1 | 1 W Wilmington | Clinton, OH | |
| 22:24 UTC | TORNADO 0 | 3 Nne Lebanon | Warren, OH | NWS SURVEY CONFIRMS BRIEF EF0 TORNADO WITH MINOR TREE AND STRUCTURAL DAMAGE |
| 22:25 UTC | HAIL 1 | Batavia | Clermont, OH | |
| 22:30 UTC | FUNNEL CLOUD | 2 N Lebanon | Warren, OH | |
| 22:33 UTC | FUNNEL CLOUD | 1 E Lebanon | Warren, OH | |
| 23:00 UTC | FLASH FLOOD | 3 S Harrison | Hamilton, OH | HIGH WATER FLOWING OVER LAWRENCEBURG ROAD IN MIAMI TOWNSHIP. |
| 23:00 UTC | FLASH FLOOD | 5 Ne Cleves | Hamilton, OH | ALMOST A FOOT OF FLOWING WATER OVER THE ROAD NEAR THE INTERSECTION OF HARRISON AVENUE AND WESSELMAN ROAD. ROAD ALSO CLOSED AT THE SAME TIME NEAR HARRISON AND RYBOLT ROAD TO TO HIGH WATER. BOTH INTERSECTIONS CLOSED BY COU |
| 23:02 UTC | TSTM WND DMG | 1 Nw Lebanon | Warren, OH | HOME WITH MINOR DAMAGE |
| 23:30 UTC | FLASH FLOOD | 3 Ene Harrison | Hamilton, OH | ABOUT 1 FOOT OF WATER FLOWING OVER MOUNT HOPE ROAD IN CROSBY TOWNSHIP. ROAD CLOSED BY COUNTY ENGINEERS OFFICE. |
| 23:57 UTC | TSTM WND DMG | 2 Sse Pleasant Plain | Clermont, OH | TREE FELL ON ROOF OF HOUSE. |
| 00:25 UTC | FLOOD | Sharonville | Hamilton, OH | FLOODING OF ROADS AND PROPERTY AFTER 2.06 INCHES OF RAIN. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2012 tornado in OhioEvery tornado in Ohio since 1950Warnings in force in Ohio nowThe forecast where you are
The other tornadoes of May 1, 2012
16 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 1 | 1:30 AM CDT | EF2 | Craig, OK | 1.0 | 150 | 1 | $250,000 | |
| May 1 | 2:33 PM EDT | EF0 | Clay, IN | 0.1 | 50 | $3,000 | ||
| May 1 | 4:45 PM EDT | EF0 | Trimble, KY | 1.9 | 15 | $25,000 | ||
| May 1 | 3:59 PM CDT | EF0 | Piatt, IL | 0.1 | 10 | |||
| May 1 | 4:06 PM CDT | EF1 | Champaign, IL | 8.1 | 75 | $25,000 | ||
| May 1 | 5:28 PM EDT | EF1 | Franklin, IN | 1.3 | 100 | $250,000 | ||
| May 1 | 4:40 PM CDT | EF0 | Champaign, IL | 0.1 | 20 | |||
| May 1 | 4:48 PM CDT | EF0 | Pope, MN | 0.1 | 50 | |||
| May 1 | 4:56 PM CDT | EF0 | Stearns, MN | 0.9 | 75 | |||
| May 1 | 5:05 PM CDT | EF0 | Stearns, MN | 2.1 | 75 | $100,000 | ||
| May 1 | 5:18 PM CDT | EF0 | Vermilion, IL | 0.5 | 30 | $8,000 | ||
| May 1 | 6:20 PM EDT | EF0 | Warren, OH | 0.0 | 10 | $5,000 | ||
| May 1 | 5:40 PM CDT | EF0 | Wright, MN | 0.0 | 25 | |||
| May 1 | 6:57 PM EDT | EF0 | Fountain, IN | 0.1 | 50 | |||
| May 1 | 7:36 PM EDT | EF1 | Montgomery, IN | 0.5 | 150 | $48,000 | ||
| May 1 | 9:40 PM CDT | EF0 | Clay, IA | 2.6 | 50 | $5,000 |
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.