Tornadoes · United States · Illinois · 1982

F0 tornado, McLean County, Illinois, August 24, 1982

This F0 tornado ran 13.0 miles across McLean County on August 24, 1982, touching down at 2:35 PM CDT and reaching 300 yards wide. It killed nobody, and did $500,000 to $5 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 mphthis tornado

    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 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
F0
Date
August 24, 1982
Touchdown
2:35 PM CDT (19:35 UTC)
Path length
13.0 miles (20.9 km)
Path width
300 yards (274 m)
Deaths
0
Injuries
0
Property damage
$500,000 to $5 million
County
McLean County
Touchdown point
40.470, -88.830
Lift-off point
40.430, -88.550
Record number
875

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.

Peoria Regional, IL (KPIA), 12:00Z

7.6 hours before the tornado, 81 km from the path. August 24, 1982.

Skew-T log-pSkew-T log-p diagram, Peoria Regional, IL at 12:00Z on 1982-08-24Temperature 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 -5710, lifted condensation level 828 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, Peoria Regional, IL at 12:00Z on 1982-08-24The 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 27 square meters per square second, 0 to 6 km bulk shear 39 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
0 J/kg
Mixed-layer CIN
-5710 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
828 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
27 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
2.7 K/km

Open this sounding in Storm Lab

Peoria Regional, IL (KPIA), 00:00Z

4.4 hours after it, 81 km from the path. August 25, 1982.

Skew-T log-pSkew-T log-p diagram, Peoria Regional, IL at 00:00Z on 1982-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 61 joules per kilogram, CIN -127, lifted condensation level 970 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, Peoria Regional, IL at 00:00Z on 1982-08-25The 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 30 square meters per square second, 0 to 6 km bulk shear 61 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
61 J/kg
Mixed-layer CIN
-127 J/kg
Surface CAPE
600 J/kg
Mixed-layer LCL
970 m above ground
0-6 km bulk shear
61 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
113 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3
0-3 km lapse rate
6.0 K/km

Open this sounding in Storm Lab

The surface observations

Bloomington/Norm (BMI), 19 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
17:56 UTC130° 10 kt1010.8
18:00 UTC140° 15 kt1010.8
18:10 UTC120° 10 kt1010.2
18:19 UTC110° 10 kt1009.5
19:00 UTC60° 10 kt1008.5
19:09 UTC150° 21 kt1005.1
19:53 UTC10° 10 kt1009.8
20:00 UTC20° 20 kt1010.2
20:10 UTC30° 7 kt1009.8
21:00 UTC120° 8 kt1009.1

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

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 August 24, 1982

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 242:25 PM CDTF2McLean, IL23.5300$500,000 to $5 million
August 242:30 PM CDTF0McLean, IL12.5300$500,000 to $5 million
August 242:35 PM CDTF0McLean, IL11.5300$50,000 to $500,000
August 243:29 PM CDTF0Ford, IL0.833$50,000 to $500,000
August 249:40 PM EDTF1Ross, OH3.5505$500,000 to $5 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.