F0 tornado, Stoughton, Wisconsin, June 18, 2006

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.

Rating

F0

Date

June 18, 2006

Touchdown

2:22 PM CDT (19:22 UTC)

Path length

0.1 miles (0.2 km)

Path width

20 yards (18 m)

Deaths

0

Injuries

0

County

Dane County

Touchdown point

42.880, -89.270

Lift-off point

42.880, -89.270

Record number

647

On a day one would not expect any tornadoes, a couple tornadoes did manage to spin up in southern Wisconsin. A fairly abnormal weather situation developed during the early afternoon hours of June 18th. After a large area of stratiform rain moved east out of Wisconsin, a line of scattered thunderstorms developed on the western edge of the rain shield. Two storms developed supercellular characteristics and produced a couple tornadoes - one that moved from Dodge County into Washington County, and another brief one in Dane county. In addition, a couple funnel clouds were reported. Specific details of both tornadoes are found above. Synoptically, a trough pushed through south-central and southeast Wisconsin during the late morning and afternoon hours. A moist airmass left behind from morning rain allowed for low cloud base heights. Sufficient low-level vertical wind shear was present for rotating storms. Once rotation was evident in the thunderstorms, tornadoes were easily formed because of low cloud heights and decent low-level CAPE.

A brief tornado spun up at 1322CST at a location 3.4 miles southwest of Stoughton, just northeast of the intersection of CTH A and Lake Kegonsa Rd. Only some tree and shrub damage was noted and the tornado was rated F0 with winds of 35-63 knots (40-72 mph). The parent thunderstorm eventually moved east and generated another funnel cloud southeast of Stoughton.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

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 Storm Prediction Center had this point in a General Thunderstorms Risk. The outlook in force was issued at 16:16 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 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.

Madison (MSN), 30 km from the path, in the two hours either side.

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

The Milwaukee radar (KMKX), 59 km away, was scanning. The volume nearest the touchdown began at 19:22 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.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2006 tornado in WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin nowThe forecast where you are

2 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.