F0 tornado, Green Bay, Wisconsin, June 23, 2004

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 23, 2004

Touchdown

9:27 PM CDT (02:27 UTC)

Path length

0.1 miles (0.2 km)

Path width

10 yards (9 m)

Deaths

0

Injuries

0

County

Brown County

Touchdown point

44.520, -88.020

Lift-off point

44.520, -88.020

Record number

1376

Thunderstorms that developed ahead of a strong cold front that moved through Wisconsin produced severe weather in the central and east central parts of the state during the evening. A line of thunderstorms tore the roof from a barn, downed numerous trees and power lines and blew a pickup truck into a ditch as the storms moved through the Wood county communities of Vesper, Nekoosa, and Wisconsin Rapids. Glass fragments caused a minor injury to one of the occupants of the pickup truck. The storms also produced 7 minutes of dime size hail 1 mile east of Wisconsin Rapids. The storms also damaged several buildings 4 miles west of Stevens Point (Portage co.), downed trees in Saxeville (Waushara co.) and dropped quarter size hail in Plover (Portage co.).As the storms moved through Portage county three tornadoes touched down. One of the tornadoes caused minor tree damage in an industrial park in Whiting. Eyewitnesses observed water being sucked out of a pond at the same time as doors to an office were sucked open. Another tornado downed several trees, knocked down a fence, damaged the roof of a house and damaged some outbuildings as it passed north of Almond. The third tornado was the strongest and was on the ground intermittently for 10 miles from southeast Portage county into southwest Waupaca county. It downed trees and overturned an irrigation system in Portage county. It strengthened in Waupaca county where it scoured asphalt off a road, destroyed a barn, sheared off the top 50 feet of a silo, crushing three calves, damaged a sheet metal outbuilding and killed 3 sheep. It tore the roof from a house and destroyed the garage, overturned a semi trailer and moved it 50 feet, blew hay wagons against trees and snapped off or uprooted numerous trees. Some of the debris from this tornado landed several miles east in the Fremont area (Waupaca co.).A tornado touched down in at least four locations from Little Chute to Kaukauna as the storms moved across Outagamie county. It toppled or twisted large trees, ripped parts of the roofs from residential and commercial buildings, destroyed storage sheds and an old barn and overturned semi trailers and dropped some of them on other vehicles.A brief tornado touchdown also occurred on the west side of Green Bay (Brown co.) where it caused some tree damage.

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

13 minutes of warning. NWS GRB issued a tornado warning for this county at 02:14 UTC, 13 minutes before the tornado touched down, in force until 03:00 UTC.

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 Moderate Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:36 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.

The Green Bay radar (KGRB), 8 km away, was scanning. The volume nearest the touchdown began at 02:27 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 2004 tornado in WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin nowThe forecast where you are

23 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.