Tornadoes · United States · Indiana · 2002

F2 tornado, Wadesville, Indiana, September 20, 2002

This F2 tornado ran 4.7 miles across Posey County on September 20, 2002, touching down at 10:50 AM CDT and reaching 150 yards wide. It killed nobody and injured 1, and did $500,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mph

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. F173 to 112 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. F2113 to 157 mphthis tornado

    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. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. F5261 to 318 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
F2
Date
September 20, 2002
Touchdown
10:50 AM CDT (15:50 UTC)
Path length
4.7 miles (7.6 km)
Path width
150 yards (137 m)
Deaths
0
Injuries
1
Property damage
$500,000
County
Posey County
Touchdown point
38.100, -87.830
Lift-off point
38.150, -87.780
Record number
289

What the Weather Service recorded

The tornado destroyed 10 mobile homes and four buildings. The greatest concentration of damage was on Highway 165 about 2 miles south of Poseyville. Peak winds were estimated around 130 MPH. Among the destroyed structures was a county highway garage. Eight vehicles were tossed, including a small van that was thrown onto a debris pile. One person was treated for a cut.

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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 12:07 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.

Lincoln, IL (KILX), 12:00Z

3.8 hours before the tornado, 235 km from the path. September 20, 2002.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 12:00Z on 2002-09-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 429 joules per kilogram, CIN 0, lifted condensation level 454 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, Lincoln, IL at 12:00Z on 2002-09-20The 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 163 square meters per square second, 0 to 6 km bulk shear 41 knots.1939587897Sfc1 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
429 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
659 J/kg
Mixed-layer LCL
454 m above ground
0-6 km bulk shear
41 kt
0-1 km bulk shear
30 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
174 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.2
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

Lincoln, IL (KILX), 00:00Z

8.2 hours after it, 235 km from the path. September 21, 2002.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2002-09-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 29 joules per kilogram, CIN -3, lifted condensation level 751 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, Lincoln, IL at 00:00Z on 2002-09-21The 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 27 square meters per square second, 0 to 6 km bulk shear 23 knots.1939587897117136Sfc1 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
29 J/kg
Mixed-layer CIN
-3 J/kg
Surface CAPE
202 J/kg
Mixed-layer LCL
751 m above ground
0-6 km bulk shear
23 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
72 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

The surface observations

Evansville (EVV), 26 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
13:54 UTC7371200° 5 kt1008.5
14:54 UTC7573 5 kt1007.8BR
15:01 UTC75.273.4170° 7 kt1007.5BR
15:28 UTC7773.4180° 10 kt161007.1BR
15:54 UTC7873190° 13 kt191007.1HZ
17:23 UTC69.866.2320° 14 kt231008.5+RA BR

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

This ground now

The live radar over the trackEvery 2002 tornado in IndianaEvery tornado in Indiana since 1950Warnings in force in Indiana nowThe forecast where you are

The other tornadoes of September 20, 2002

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 2010:40 AM CDTF0Posey, IN0.240
September 2011:35 AM ESTF2Pike, IN13.51502$1.0 million
September 2012:59 PM ESTF3Monroe, IN112.0150127$103 million
September 202:47 PM ESTF2Henry, IN6.0100$2.0 million
September 203:03 PM ESTF0Rush, IN1.0100$500,000
September 204:41 PM EDTF1Allen, OH0.125$50,000
September 205:15 PM EDTF0Van Wert, OH4.0100

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.