Tornadoes · United States · Wisconsin · 2002
F1 tornado, Eden, Wisconsin, September 2, 2002
This F1 tornado ran 0.3 miles across Fond du Lac County on September 2, 2002, touching down at 9:30 PM CDT and reaching 75 yards wide. It killed nobody, and did $750,000 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.
F040 to 72 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F173 to 112 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
F4207 to 260 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- September 2, 2002
- Touchdown
- 9:30 PM CDT (02:30 UTC)
- Path length
- 0.3 miles (0.5 km)
- Path width
- 75 yards (69 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $750,000
- County
- Fond du Lac County
- Touchdown point
- 43.720, -88.370
- Lift-off point
- 43.720, -88.370
- Record number
- 856
What the Weather Service recorded
Clusters or short lines of severe storms with powerful downburst winds and isolated tornadoes moved through parts of south-central and southeast Wisconsin on Labor Day September 2, 2002. Two tornadoes spun up in Fond du Lac County. Refer to those individual tornado events for details. Numerous large trees were toppled in some locations by the downburst winds, while broken tree branches snapped some power lines. Amateur radio operators in Waukesha County measured peak wind gust of 58 knots (67 mph). In West Bend (Washington Co.), a house trailer was blown over, and slightly damaged, by the powerful winds.
A tornado, rated as F1 with winds of about 78 to 87 knots (90 to 100 mph) damaged three, large, cover-all, dairy barns. Severe damage was noted on the western-most barn. In addition, some trees were uprooted or had limbs ripped off. The three barns were part of Fond du Lac's largest dairy farm. Luckily, only one of the 1400 dairy cows was injured.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
23 minutes of warning. NWS MKX issued a tornado warning for this county at 02:07 UTC, 23 minutes before the tornado touched down, in force until 03:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 02:03 UTC | 03:00 UTC | Severe Thunderstorm Warning | MKX |
| 02:07 UTC | 03:00 UTC | Tornado Warning | MKX |
| 02:07 UTC | 03:00 UTC | Tornado Warning | MKX |
| 02:55 UTC | 03:30 UTC | Severe Thunderstorm Warning | MKX |
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 Moderate Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:20 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.
Green Bay/Straub, WI (KGRB), 00:00Z
2.5 hours before the tornado, 87 km from the path. September 3, 2002.
- Mixed-layer CAPE
- 1990 J/kg
- Mixed-layer CIN
- -95 J/kg
- Surface CAPE
- 2569 J/kg
- Mixed-layer LCL
- 1037 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 201 m²/s²
- 0-3 km storm-relative helicity
- 193 m²/s²
- Significant tornado parameter
- 1.5
- Supercell composite
- 5.9
- 0-3 km lapse rate
- 5.4 K/km
Green Bay/Straub, WI (KGRB), 12:00Z
9.5 hours after it, 87 km from the path. September 3, 2002.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -58071 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 1322 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- -20 m²/s²
- 0-3 km storm-relative helicity
- 92 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 3.3 K/km
The surface observations
Fond Du Lac (FLD), 11 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 00:53 UTC | 77 | 72 | 200° 10 kt | 1006.1 | HZ | |
| 01:53 UTC | 77 | 72 | 200° 10 kt | 1005.1 | HZ | |
| 02:26 UTC | 71.6 | 69.8 | 290° 23 kt | 34 | 1008.1 | RA BR |
| 02:29 UTC | 66.2 | 66.2 | 300° 23 kt | 36 | 1008.1 | +RA BR |
| 02:31 UTC | 64.4 | 64.4 | 300° 19 kt | 36 | 1008.1 | +RA BR |
| 02:42 UTC | 66.2 | 66.2 | 200° 7 kt | 1007.8 | -RA BR | |
| 02:45 UTC | 66.2 | 66.2 | 200° 9 kt | 14 | 1008.5 | -RA BR |
| 02:53 UTC | 67 | 66 | 210° 10 kt | 1008.5 | -RA | |
| 03:53 UTC | 67 | 67 | 270° 5 kt | 1008.8 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Milwaukee radar (KMKX), 85 km away, was scanning. The volume nearest the touchdown began at 02:31 UTC.
Open the radar archive at this moment, over the track
Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.
This ground now
The live radar over the trackEvery 2002 tornado in WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin nowThe forecast where you are
The other tornadoes of September 2, 2002
5 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| September 2 | 4:22 PM CDT | F3 | Rusk, WI | 16.0 | 440 | 27 | $25 million | |
| September 2 | 5:10 PM CDT | F2 | Taylor, WI | 17.0 | 75 | $3.9 million | ||
| September 2 | 6:04 PM CDT | F0 | Marathon, WI | 0.2 | 75 | |||
| September 2 | 6:35 PM CDT | F1 | Marathon, WI | 5.0 | 200 | 1 | $1.3 million | |
| September 2 | 9:06 PM CDT | F0 | Fond du Lac, WI | 0.1 | 30 |
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.