Tornadoes · United States · Ohio · 2012

EF0 tornado, Blackhawk, Ohio, March 23, 2012

This EF0 tornado ran 0.4 miles across Warren County on March 23, 2012, touching down at 8:30 PM EDT and reaching 50 yards wide. It killed nobody, and did $20,000 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
March 23, 2012
Touchdown
8:30 PM EDT (00:30 UTC)
Lifted
8:31 PM EDT (00:31 UTC)
On the ground
1 minutes
Path length
0.4 miles (0.7 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$20,000
County
Warren County
Touchdown point
39.322, -84.070
Lift-off point
39.326, -84.064
Record number
1203231830-01

What the Weather Service recorded

An approaching upper level low pressure system combined with daytime heating to produce scattered thunderstorms across the Ohio Valley during the afternoon and evening. An environment with moderate instability and strong low level shear allowed thunderstorms to become severe, leading to the possibility of large hail, damaging winds, and weak tornadoes.

The tornado touched down and caused damage to a pole barn, where roofing was removed and strewn downstream nearly a quarter of a mile. Some wood from the barn was blown upstream of the tornado path and driven into the roof of the residence where the barn was damaged. The tornado then caused damage mainly to trees, with several trees uprooted or snapped off. Based on the damage surveyed, the maximum estimated wind speed of the tornado was 75 miles per hour.

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.

Issued (UTC)ExpiredProductOffice
22:39 UTC23:15 UTCSevere Thunderstorm WarningILN

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, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:53 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

0.5 hours before the tornado, 26 km from the path. March 24, 2012.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 00:00Z on 2012-03-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 672 joules per kilogram, CIN -1, lifted condensation level 552 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2012-03-24The 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 133 square meters per square second, 0 to 6 km bulk shear 39 knots.19395878Sfc1 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
672 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
1193 J/kg
Mixed-layer LCL
552 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
155 m²/s²
Significant tornado parameter
0.4
Supercell composite
3.2
0-3 km lapse rate
6.1 K/km

Open this sounding in Storm Lab

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

11.5 hours after it, 26 km from the path. March 24, 2012.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 12:00Z on 2012-03-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1 joules per kilogram, CIN -102, lifted condensation level 783 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2012-03-24The 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 2 square meters per square second, 0 to 6 km bulk shear 34 knots.19395878Sfc1 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
1 J/kg
Mixed-layer CIN
-102 J/kg
Surface CAPE
21 J/kg
Mixed-layer LCL
783 m above ground
0-6 km bulk shear
34 kt
0-1 km bulk shear
2 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
10 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

The radar

The Cincinnati radar (KILN), 24 km away, was scanning. The volume nearest the touchdown began at 00:29 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
22:42 UTCTSTM WND DMG3 Se MilfordClermont, OHTREES REPORTED DOWN ON BEECHWOOD ROAD AND BALDWIN ROAD. TIME ESTIMATED BY RADAR.
23:30 UTCTORNADO5 Wnw BlanchesterWarren, OHA BRIEF TORNADO TOUCHED DOWN NEAR THE INTERSECTION OF HIGHWAYS 123 AND 132 IN HARLAN TOWNSHIP.
23:33 UTCTSTM WND DMG5 Wnw BlanchesterWarren, OHPOLE BARN DESTROYED. WIRES AND TREES DOWN. CORRECTED TIME BASED ON RADAR.
23:48 UTCTSTM WND DMG5 Wnw BlanchesterWarren, OHPOLE BARN DESTROYED. WIRES AND TREES DOWN.
23:50 UTCTORNADOClarksvilleClinton, OHA BRIEF TORNADO TOUCHED DOWN IN THE VILLAGE OF CLARKSVILLE.
23:55 UTCTSTM WND DMGClarksvilleClinton, OHDAMAGE TO THREE STRUCTURES INCLUDING A LARGE LIMB DOWN ON A HOUSE. ALSO REPORTS OF TREE DAMAGE AND POWER LINES DOWN. CORRECTED TIME.
00:10 UTCTSTM WND DMGClarksvilleClinton, OHDAMAGE TO THREE STRUCTURES INCLUDING A LARGE LIMB DOWN ON A HOUSE. ALSO REPORTS OF TREE DAMAGE AND POWER LINES DOWN. TIME ESTIMATED FROM RADAR.

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 March 23, 2012

13 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 239:26 AM CDTEF1Pike, AL1.7700
March 2311:33 AM CDTEF0Cape Girardeau, MO0.350$10,000
March 2311:38 AM CDTEF1Cape Girardeau, MO0.6300
March 2312:14 PM CDTEF0Jackson, IL1.850
March 2312:24 PM CDTEF1Jackson, IL7.5125$75,000
March 2312:48 PM CDTEF0Geneva, AL1.725$25,000
March 231:26 PM CDTEF2Jefferson, IL2.610012$150,000
March 231:57 PM CDTEF0Marion, IL0.010
March 233:07 PM EDTEF1Jefferson, KY2.470$300,000
March 233:20 PM EDTEF0Early, GA3.525$5,000
March 233:28 PM EDTEF1Shelby, KY2.250$25,000
March 234:30 PM EDTEF0Switzerland, IN0.125
March 237:50 PM EDTEF0Clinton, OH0.450$50,000

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.