F1 tornado, Bay City to Bayou, Illinois, September 22, 2006

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.

Rating

F1

Date

September 22, 2006

Touchdown

4:02 PM CDT (21:02 UTC)

Path length

9.3 miles (15.0 km)

Path width

500 yards (457 m)

Deaths

0

Injuries

0

Property damage

$365,000

Counties

Livingston and Pope counties

Touchdown point

37.230, -88.520

Lift-off point

37.300, -88.350

Record number

906

This tornado originated in Pope County and crossed the Ohio River into Livingston County, Kentucky. Two distinct paths of mainly tree damage were found south of Bay City in Pope County. Both showed signs of convergence, and this appeared to be the result of a multiple vortex tornado. The main damage path was about 300 yards wide with peak winds of 80 MPH. The second damage path was about two-tenths of a mile south of the first path and was about 100 yards wide. Peak winds with this path were estimated near 75 MPH. Mainly tree damage was seen with the second vortex. Citizens reported one tornado crossing the Ohio River into Kentucky. A camper on a bluff in the Shawnee National Forest videotaped the tornado after it crossed the river. A radio tower, numerous trees, and some power lines were down in the Bay City area.

The tornado crossed the Ohio River from Pope County, Illinois into Livingston County in densely forested areas interspersed with some farmland. The average width of this upper-end F1 tornado was close to 300 yards. Peak winds were estimated near 110 MPH. One mobile home was destroyed, and roofs were partially torn off two houses. Eighteen homes sustained minor damage, consisting mostly of roofing and siding blown off. Twenty barns were heavily damaged or destroyed. Six silos were destroyed, including two of rebar-reinforced concrete construction. The tornado was videotaped by a camper from a bluff overlooking the Ohio River. The footage was shot from within Pope County, Illinois looking east across the river.

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

34 minutes of warning. NWS PAH issued a tornado warning for this county at 20:28 UTC, 34 minutes before the tornado touched down, in force until 21:15 UTC.

The county was under a tornado watch, issued at 20:37 UTC and running to 05:00 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 0.15 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 19:56 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 Paducah radar (KPAH), 37 km away, was scanning. The volume nearest the touchdown began at 21:00 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 IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

32 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.