EF2 tornado, Peotone, Illinois, October 26, 2010

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mphthis tornado

   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. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 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

EF2

Date

October 26, 2010

Touchdown

7:40 AM CDT (12:40 UTC)

Lifted

7:44 AM CDT (12:44 UTC)

On the ground

4 minutes

Path length

2.3 miles (3.7 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

2

Property damage

$500,000

County

Will County

Touchdown point

41.309, -87.739

Lift-off point

41.340, -87.723

Record number

1010260640-01

A line of strong to severe thunderstorms moved across northern Illinois during the morning hours of October 26th. Three tornadoes were reported along with damaging winds.

A tornado touched down about 4 miles east of Peotone. The tornado produced its most intense damage along South Will Center Road, about halfway between Corning Road and Peotone-Beacher Road, removing a house's roof, collapsing exterior walls on the second floor of the house, and completely destroying a garage and three other outbuildings. Two teenage boys were injured in the house. Four power poles were also downed just northeast of the area along Peotone-Beecher Road. Additional EF1 and EF0 damage was found along a path running southwest toward Kennedy Road. This damage consisted of collapsed outbuildings, snapped cedar trees, and damage to homes. One home on Corning Road was pushed off its foundation and the chimney collapsed.

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

3 minutes of warning. NWS LOT issued a tornado warning for this county at 12:37 UTC, 3 minutes before the tornado touched down, in force until 13:00 UTC.

The county was under a tornado watch, issued at 08:37 UTC and running to 13:23 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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 06:06 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 Chicago radar (KLOT), 43 km away, was scanning. The volume nearest the touchdown began at 12:40 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 2010 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

60 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.