Tornadoes · United States · Illinois · 1982

F4 tornado, Williamson County, Illinois, May 29, 1982

This F4 tornado ran 17.0 miles across Williamson County on May 29, 1982, touching down at 3:05 PM CDT and reaching 400 yards wide. It killed 10 people and injured 181, and did $50 million to $500 million 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 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. 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 mphthis tornado

    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
F4
Date
May 29, 1982
Touchdown
3:05 PM CDT (20:05 UTC)
Path length
17.0 miles (27.4 km)
Path width
400 yards (366 m)
Deaths
10
Injuries
181
Property damage
$50 million to $500 million
County
Williamson County
Touchdown point
37.800, -89.130
Lift-off point
37.720, -88.830
Record number
530

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.

Salem-Leckrone, IL (KSLO), 12:00Z

8.1 hours before the tornado, 99 km from the path. May 29, 1982.

Skew-T log-pSkew-T log-p diagram, Salem-Leckrone, IL at 12:00Z on 1982-05-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -6985, lifted condensation level 1680 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Salem-Leckrone, IL at 12:00Z on 1982-05-29The 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 40 knots.193958Sfc1 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
0 J/kg
Mixed-layer CIN
-6985 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1680 m above ground
0-6 km bulk shear
40 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
201 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.1 K/km

Open this sounding in Storm Lab

Salem-Leckrone, IL (KSLO), 00:00Z

3.9 hours after it, 99 km from the path. May 30, 1982.

Skew-T log-pSkew-T log-p diagram, Salem-Leckrone, IL at 00:00Z on 1982-05-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1093 joules per kilogram, CIN -9, lifted condensation level 817 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, Salem-Leckrone, IL at 00:00Z on 1982-05-30The 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 70 square meters per square second, 0 to 6 km bulk shear 35 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
1093 J/kg
Mixed-layer CIN
-9 J/kg
Surface CAPE
2491 J/kg
Mixed-layer LCL
817 m above ground
0-6 km bulk shear
35 kt
0-1 km bulk shear
24 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
107 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.6
0-3 km lapse rate
6.0 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1982 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

The other tornadoes of May 29, 1982

11 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 294:00 AM CDTF1Boone, MO0.120$500 to $5,000
May 292:30 PM EDTF1Greene, OH0.350$50,000 to $500,000
May 292:05 PM CDTF3Perry, IL10.02007$50,000 to $500,000
May 293:20 PM MDTF2Washington, CO1.5100$50 to $500
May 293:24 PM MDTF1Adams, CO0.550
May 294:26 PM CDTF0Saline, IL0.110under $50
May 294:46 PM CDTF0Saline, IL0.110$50 to $500
May 295:10 PM CDTF1Gibson, IN0.110$50,000 to $500,000
May 296:10 PM MDTF2Lincoln, CO1.0100
May 296:52 PM MDTF1Scotts Bluff, NE0.520under $50
May 297:32 PM MDTF1Morrill, NE0.330under $50

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.