Tornadoes · United States · Kansas · 1985

F0 tornado, Lyon County, Kansas, August 17, 1985

This F0 tornado ran 0.1 miles across Lyon County on August 17, 1985, touching down at 6:23 PM CDT and reaching 10 yards wide. It killed nobody.

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 17, 1985
Touchdown
6:23 PM CDT (23:23 UTC)
Path length
0.1 miles (0.2 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
County
Lyon County
Touchdown point
38.720, -96.250
Record number
576

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.

Topeka, KS (KTOP), 12:00Z

11.4 hours before the tornado, 61 km from the path. August 17, 1985.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 12:00Z on 1985-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 954 joules per kilogram, CIN -15, lifted condensation level 562 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, Topeka, KS at 12:00Z on 1985-08-17The 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 -125 square meters per square second, 0 to 6 km bulk shear 16 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
954 J/kg
Mixed-layer CIN
-15 J/kg
Surface CAPE
402 J/kg
Mixed-layer LCL
562 m above ground
0-6 km bulk shear
16 kt
0-1 km bulk shear
34 kt
0-1 km storm-relative helicity
-125 m²/s²
0-3 km storm-relative helicity
-146 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.6 K/km

Open this sounding in Storm Lab

Topeka, KS (KTOP), 00:00Z

0.6 hours after it, 61 km from the path. August 18, 1985.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 00:00Z on 1985-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3706 joules per kilogram, CIN -7, lifted condensation level 915 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, Topeka, KS at 00:00Z on 1985-08-18The 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 65 square meters per square second, 0 to 6 km bulk shear 36 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
3706 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
3276 J/kg
Mixed-layer LCL
915 m above ground
0-6 km bulk shear
36 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
1.9
Supercell composite
8.6
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The surface observations

Emporia (EMP), 44 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:00 UTC8776140° 15 kt1012.5
23:00 UTC8776140° 14 kt1012.2
23:23 UTC140° 15 kt1012.2
00:00 UTC8475140° 14 kt1011.2TS
00:52 UTC360° 35 kt451012.5
01:00 UTC7976 1011.9TSRA FG
01:01 UTC360° 20 kt301013.9
01:14 UTC140° 15 kt251014.6

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

This ground now

The live radar over the trackEvery 1985 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

The other tornadoes of August 17, 1985

10 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 177:50 AM EDTF1Jackson, GA10.070$500,000 to $5 million
August 178:40 AM EDTF1Oconee, GA6.030$50,000 to $500,000
August 1712:50 PM EDTF2Spartanburg, SC9.010039$500,000 to $5 million
August 172:55 PM EDTF1York, SC3.030$50,000 to $500,000
August 173:00 PM EDTF0York, SC1.030$50,000 to $500,000
August 173:15 PM EDTF0Union, SC3.030$5,000 to $50,000
August 176:18 PM CDTF3Wabaunsee, KS2.050$50,000 to $500,000
August 177:26 PM CDTF1Waukesha, WI15.050$50,000 to $500,000
August 177:28 PM CDTF0Lyon, KS0.210
August 1712:45 AM EDTF0Chatham, NC4.0100$5,000 to $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.