Unrated tornado, Symerton to Peotone, Illinois, July 28, 2023

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 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. Unratedthis tornado

   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

Unrated

Date

July 28, 2023

Touchdown

11:22 PM CDT (04:22 UTC)

Lifted

11:24 PM CDT (04:24 UTC)

On the ground

2 minutes

Path length

1.5 miles (2.3 km)

Path width

15 yards (14 m)

Deaths

0

Injuries

0

County

Will County

Touchdown point

41.300, -87.803

Lift-off point

41.303, -87.775

Record number

2307282222-01

143 damage points were recorded along this path by NWS LOT, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 110 mph.

• numerous large branches downed onto house
• numerous trees with large branches downed, some trunks snapped. Metal sign damaged.
• trees uprooted, several branches downed, narrow corridor
• No structural damage noted

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

July 28th saw two rounds of severe storms move across the Chicago metro, one during the predawn hours of the morning and another during the evening. The first round brought isolated instances of damaging wind to the area and the second featured damaging winds, severe hail, and 13 tornadoes across the WFO Chicago CWA: 11 in Illinois and 2 in Indiana. Additionally, temperatures in the 90s and high humidity resulted in oppressively hot conditions with afternoon heat indices as high as 105-115��F.

To the east of the tornado that lifted over Midewin National Tallgrass Prairie, a second tornado began near South Warner Bridge Road between Wilton Center and West Doyle Roads. Here, several trees were uprooted and numerous large limbs were downed. One tree fell onto a residence, resulting in roof damage. Shingle loss and damage to gutters, siding, fascia, and soffit were all consistent with high-end EF-0 winds near 85 mph. The tornado tracked nearly due east to the north of West Arsenal Road, causing intermittent minor damage to corn and trees. The tornado moved southeast and crossed West Arsenal Road just west of US Route 52. At this point, the tornado was likely less than 15 yards wide with winds around 60 mph. It continued eastward, crossing north of West Joliet Road near Laughton Preserve. The tornado appeared to have continued east a few more miles before dissipating in a field just west of US Route 45.

Drone footage and high resolution satellite data revealed that a tornado touched down near north of E 12000N Road just east of S Rathje Road south of Peotone and lifted in a field between S Drecksler Road and S Ridgeland Avenue. This tornado was on the ground for less than 2 minutes and was around 15 yards wide. The only damage noted was to crops, namely soybeans.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

The county was under a severe thunderstorm watch, issued at 00:31 UTC and running to 05:44 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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 00:53 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), 42 km away, was scanning. The volume nearest the touchdown began at 04:19 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 2023 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

16 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.