EF2 tornado, Windsor to Oakland, Illinois, December 10, 2021

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

December 10, 2021

Touchdown

9:50 PM CST (03:50 UTC)

Lifted

10:04 PM CST (04:04 UTC)

On the ground

14 minutes

Path length

15.9 miles (25.5 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

0

Counties

Shelby, Moultrie and Coles counties

Touchdown point

39.419, -88.590

Lift-off point

39.536, -88.335

Record number

2112102150-01

20 damage points were recorded along this path by NWS ILX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 125 mph.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A deepening area of low pressure tracked from near Kansas City during the afternoon of December 10th to southern Lake Michigan by the pre-dawn hours of December 11th. An unseasonably warm and moist airmass surged northward ahead of the system, resulting in high temperatures reaching the lower to middle 60s across central Illinois. As the low and an associated vigorous short-wave trough interacted with the moderately unstable and highly sheared environment, several clusters of strong to severe thunderstorms developed during the late afternoon and evening of the 10th. Numerous rotating cells were observed, with a total of 6 tornadoes touching down across central Illinois. 5 of the tornadoes were rated EF-2, including one that injured a person just north of Herrick in Shelby County.

A tornado touched down 1 mile south of Windsor at 9:50 PM CST. The tornado stripped roof panels off a farm outbuilding, then tracked northeastward and strengthened causing total destruction of a small farm outbuilding and breaking wood power poles southeast of Windsor. It crossed into southern Moultrie County about 1 mile southwest of Gays just south of Route 16 at 9:54 PM CST.

This tornado crossed from Shelby County into southern Moultrie County about 1 mile southwest of Gays at 9:54 PM CST. An agriculture services plant was significantly damaged west of Gays, with numerous buildings destroyed and 3 large tanker trucks flipped. The tornado continued northeastward and crossed into western Coles County just south of Western Avenue at 9:58 PM CST.

This tornado crossed from Moultrie County into western Coles County just south of Western Avenue at 9:58 PM CST. Several houses and outbuildings were damaged in western Coles County...from west of Mattoon to northeast of Mattoon. The most |significant damage included a one-story brick house that had it's roof entirely removed and 2 large metal storage buildings that sustained roof, siding, and metal support structure damage. The tornado lifted about 4 miles north-northeast of Mattoon at 10:04 PM.

A tornado touched down about one quarter of a mile east of Rardin at 10:18 PM CST. The tornado did only tree damage with the greatest concentration through the wooded areas along the Embarras River. Evidence that the tornado was on the ground was also found along East County Road 1750 North. The tornado lifted 1 mile east of Oakland at 10:22 PM CST.

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

27 minutes of warning. NWS ILX issued a tornado warning for this county at 03:23 UTC, 27 minutes before the tornado touched down, in force until 03:59 UTC.

The county was under a tornado watch, issued at 01:47 UTC and running to 06:16 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 Enhanced Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 00:47 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.

Mattoon/Charlest (MTO), 16 km from the path, in the two hours either side.

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

The Lincoln radar (KILX), 106 km away, was scanning. The volume nearest the touchdown began at 03:49 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 2021 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.