F2 tornado, Monticello, Illinois, October 24, 2001

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 mph

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

3. F2113 to 157 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. 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

F2

Date

October 24, 2001

Touchdown

1:35 PM CDT (18:35 UTC)

Path length

1.8 miles (2.9 km)

Path width

300 yards (274 m)

Deaths

0

Injuries

0

Property damage

$2.2 million

County

Piatt County

Touchdown point

40.030, -88.580

Lift-off point

40.050, -88.550

Record number

1112

An eyewitness reported that the tornado touched down on the southwest side of Monticello and traveled to the north northeast across town. It blew down numerous trees near the golf course then destroyed a storage building. In this area the tornado intensified to F2 Intensity (wind speeds of 120 to 130 mph) taking the roof of a church completely off and blew it into the roof of a nearby 2 story apartment building. The apartment building suffered severe damage and has been deemed uninhabitable. A farm implement building/business, which was close to 200 feet in length, had roughly three quarters of the building destroyed. Damage for this building was estimated at nearly $2 million, as several combines inside were severely damaged or destroyed. Debris from the building was thrown into a nearby power substation, causing a complete power outage to the town of 5,000 residents as well as neighboring communities. The tornado appeared to have lifted off the ground and stayed at tree top level for the remainder of its life through the town producing F0 damage. Numerous trees had the tops broken off and several large trees were uprooted. Once outside of town it did touch down briefly once more, damaging the roof of one home and destroying several outbuildings and a garage of another homestead about a mile north northeast of town. In this location, several 2 inch by 6 inch pieces of lumber from one of the machine sheds had shot through patio doors into the home. No injuries were reported due to the tornado. Damage is estimated around $2.2 million.

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

21 minutes of warning. NWS ILX issued a tornado warning for this county at 18:14 UTC, 21 minutes before the tornado touched down, in force until 19:00 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 High Risk. The outlook in force was issued at 16:00 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.

Champaign - Willard (CMI), 25 km from the path, in the two hours either side.

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

The Lincoln radar (KILX), 67 km away, was scanning. The volume nearest the touchdown began at 18:35 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.

The live radar over the trackEvery 2001 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

24 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.