Tornadoes · United States · Illinois · 2026

EF0 tornado, Lee County, Illinois, August 21, 2026

This EF0 tornado ran 0.7 miles across Lee County on August 21, 2026, touching down at 5:55 PM CDT and reaching 200 yards wide. It killed nobody.

Preliminary. This is NWS LOT's damage survey, filed in the Damage Assessment Toolkit as Henkel. The rating, the path and the casualties are the survey's and can change while it is revised. The Storm Prediction Center compiles the official record of 2026 from these surveys and publishes it in the spring of 2027; this page moves to that tornado's permanent address when it does.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mphthis tornado

    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 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. 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.

The survey

Rating, as surveyed
EF0, preliminary
Date
August 21, 2026
Touchdown
5:55 PM CDT (22:55 UTC)
Lifted
5:56 PM CDT (22:56 UTC)
On the ground
1 minutes
Path length
0.7 miles (1.1 km)
Path width
200 yards (183 m)
Deaths
0
Injuries
0
County
Lee County
Touchdown point
41.608, -89.174
Lift-off point
41.598, -89.176
Highest wind the damage implies
70 mph
Surveyed by
NWS LOT
The office's name for it
Henkel
Survey last edited
August 24, 2026
Record number
None yet. SPC numbers 2026 in the spring of 2027.

What the survey found

Based on drone footage provided by the Lee County Sheriff's office, the tornado began in an open field east of the intersection of Henkel Road and US Highway 52 and caused damage to crops. The tornado continued generally southward and damaged several roofs of buildings near the intersection of Cedar Grove Road and US Highway 52 before causing additional crop damage behind a farmstead. The tornado appeared to lift in an open field to the north of Pike Creek west of US Highway 52. The tornado was captured by video and photo by several storm chasers in the area. Thank you to both the Lee County Emergency Management Agency and Lee County Sheriff's Office for their help in completing the survey for this tornado.

Written by NWS LOT in the NWS Damage Assessment Toolkit. A survey is revised as better evidence arrives.

The damage survey

7 damage points were recorded along this path by NWS LOT, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EFU. The highest wind the damage implies is 70 mph.

  • A portion of the metal roofing removed from a building. A hay conveyer was tipped over on the north side of the property, as well.
  • Swirl marks evident in crops via drone footage
  • Approximate start point based on beginning of swirl marks in field.
  • Damage to the outer edges of metal roof structure

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

The county was under a severe thunderstorm watch, issued at 19:58 UTC and running to 02:38 UTC.

Issued (UTC)ExpiredProductOffice
19:58 UTC02:38 UTCSevere Thunderstorm WatchLOT
21:13 UTC21:53 UTCSevere Thunderstorm WarningLOT
21:55 UTC22:24 UTCSevere Thunderstorm WarningLOT
22:44 UTC23:13 UTCSevere Thunderstorm WarningLOT

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 forecast that day

The Storm Prediction Center had this point in a Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 20:00 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 air that afternoon

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.

Davenport, (KDVN), 00:00Z

1.1 hours after it, 110 km from the path. August 22, 2026.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2026-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3453 joules per kilogram, CIN -1, lifted condensation level 863 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 00:00Z on 2026-08-22The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 89 square meters per square second, 0 to 6 km bulk shear 33 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
3453 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
4908 J/kg
Mixed-layer LCL
863 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
89 m²/s²
0-3 km storm-relative helicity
165 m²/s²
Significant tornado parameter
1.2
Supercell composite
7.8
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The surface observations

Peru (VYS), 28 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:59 UTC82.466.2190° 8 kt1015.6
21:22 UTC80.668200° 5 kt1015.2
21:38 UTC78.868200° 6 kt1015.2
21:58 UTC78.868210° 7 kt1014.9
22:19 UTC78.868200° 5 kt1014.9
22:38 UTC78.868220° 5 kt1014.9
23:00 UTC78.869.8190° 5 kt1014.2
23:18 UTC78.869.8190° 4 kt1014.6
23:40 UTC7769.8170° 5 kt1013.9
23:58 UTC73.469.8350° 4 kt1014.6+RA
00:18 UTC71.669.8280° 5 kt1015.6+RA
00:38 UTC71.668210° 8 kt1014.9-RA

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

The radar

The Chicago radar (KLOT), 91 km away, was scanning. The volume nearest the touchdown began at 22:56 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
22:55 UTCTORNADO4 Se SubletteLee, ILAn NWS damage survey determined an EF-0 tornado with peak winds around 70 mph, path length of around 0.7 miles, and maximum width of around 200 yards impacted the rural community of Henkel.
22:57 UTCTORNADO4 Se SubletteLee, ILVideo shows very brief tornado just north of US-52 at Cedar Grove Road.
23:05 UTCHAIL 1.53 N MendotaLa Salle, ILMultiple photos depict hail just larger than ping pong balls. Time estimated by radar.
00:11 UTCTORNADO1 S DepuePutnam, ILCorrects previous tornado report starting location and time. An EF0 tornado, with estimated peak winds of 80 MPH, developed near the southern banks of the Illinois River and curled its way across northern Putnam County.
00:13 UTCTORNADO2 N MorontsPutnam, ILAn EF0 tornado, with peak winds of 70 MPH, developed along the southern banks of the Illinois River and moved towards the south-southeast. The tornado crossed through a rock quarry, where it tipped over a portion of an i
00:15 UTCTORNADO1 Nne MorontsPutnam, ILVideo on social media.
00:19 UTCTSTM WND DMG2 N FloridPutnam, ILTree over 12 inches in diameter blown down. Possible tornado damage. Time estimated from radar data.
00:34 UTCFUNNEL CLOUD3 S GranvillePutnam, ILBased on multiple spotter photos and reports.
01:50 UTCFLASH FLOODMarkPutnam, ILReports of street flooding at a few locations around the town of Granville.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2026 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

The other tornadoes of August 21, 2026

1 more have been surveyed in the United States that day, so far.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 217:11 PM CDTEF0Putnam, IL4.3100

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. A survey can be revised, so the rating, the path and the casualties can all still change.

Sources

NWS Damage Assessment Toolkit, the record the survey teams file from the damage, and NOAA Storm Prediction Center storm reports. Neither is the official database for 2026, which SPC publishes in the spring of 2027.