EF1 tornado, Lee County, Illinois, August 9, 2026

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 mphthis tornado

   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.

Rating, as surveyed

EF1, preliminary

Date

August 9, 2026

Touchdown

10:02 PM CDT (03:02 UTC)

Lifted

10:24 PM CDT (03:24 UTC)

On the ground

22 minutes

Path length

7.0 miles (11.2 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

0

County

Lee County

Touchdown point

41.706, -89.237

Lift-off point

41.782, -89.192

Highest wind the damage implies

90 mph

Surveyed by

NWS LOT

The office's name for it

Amboy

Survey last edited

August 25, 2026

Record number

None yet. SPC numbers 2026 in the spring of 2027.

A tornado began just east of Amboy near Shaws. This tornado tracked northeast and then turned slightly northwest as it crossed U.S. Highway 30 before dissipating south of Pipeline Road. The tornado caused damage to trees, power lines, outbuildings, and crops along its nearly 7-mile long track.

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

14 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 90 mph.

• Several hardwood trees down. From Lee County Sheriffs Office drone imagery.
• From Lee County Sheriffs Office drone imagery.
• Swirl pattern in crops. From Lee County Sheriffs Office drone imagery.
• End of the path of swirl marks in the crops from Lee County Sheriffs Office drone imagery.

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

13 minutes of warning. NWS LOT issued a tornado warning for this county at 02:49 UTC, 13 minutes before the tornado touched down, in force until 03:30 UTC.

The county was under a severe thunderstorm watch, issued at 01:44 UTC and running to 07:23 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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 00:41 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), 95 km away, was scanning. The volume nearest the touchdown began at 03:01 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 2026 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

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

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.

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.