Tornadoes · United States · Wisconsin · 1985

F1 tornado, Waukesha and Milwaukee counties, Wisconsin, August 17, 1985

This F1 tornado ran 15.0 miles across Waukesha and Milwaukee counties on August 17, 1985, touching down at 7:26 PM CDT and reaching 50 yards wide. It killed nobody, and did $50,000 to $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 mphthis tornado

    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
F1
Date
August 17, 1985
Touchdown
7:26 PM CDT (00:26 UTC)
Path length
15.0 miles (24.1 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$50,000 to $500,000
Counties
Waukesha and Milwaukee counties
Touchdown point
43.180, -88.320
Lift-off point
43.180, -88.020
Record number
577

The surface observations

Milwaukee/Lawren (MWC), 13 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

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

This ground now

The live radar over the trackEvery 1985 tornado in WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin 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 176:23 PM CDTF0Lyon, KS0.110
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.