Unrated tornado, Grant Park to Yeager, Illinois, May 7, 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

May 7, 2023

Touchdown

6:30 PM CDT (23:30 UTC)

Lifted

6:31 PM CDT (23:31 UTC)

On the ground

1 minutes

Path length

0.2 miles (0.3 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Kankakee County

Touchdown point

41.228, -87.635

Lift-off point

41.231, -87.633

Record number

2305071730-02

5 damage points were recorded along this path by NWS LOT, in the Damage Assessment Toolkit the survey teams carry.

• Video filmed from intersection of Route 1 and Route 17 shows landspout swirling dust around at this approximate location.
• Car thrown into ditch along Route 1/17. Exact location and time estimated.
• Photo shows landspout on ground behind farmstead along Route 1/17.

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

On the evening of May 7th, a line of thunderstorms produced severe winds, severe hail, heavy rain, and even two landspouts across parts of the southern and southwestern Chicago metro. The heaviest of the rainfall occurred along a narrow corridor stretching from far southern Lee County southeastward into east-central Kankakee County where widespread 2+ inch rainfall totals were reported with a few spots seeing between four and five inches of rain. Additionally, strong outflow winds from nearby thunderstorms kicked up significant amounts of blowing dust across parts of southern LaSalle County and towards the I-55 corridor in Livingston County. This was preceded by an abnormally dry period stretching back to early April leading to dry soil conditions in the area. Multiple reports of near-zero visibility resulted in the issuance of two Dust Storm Warnings, the first such warnings issued by the Chicago WFO.

A video shared shows a landspout-type tornado kicking up dust in a field southwest of Route 1 and Route 17 near Grant Park. Time was estimated based on radar.

A photo shared shows a landspout tornado occurring along State Route 1/17 between Grant Park and Momence. The landspout threw a car into a ditch but did not cause any known damage to structures or trees.

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.

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 Marginal Risk. The outlook in force was issued at 19:53 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.

Kankakee (IKK), 25 km from the path, in the two hours either side.

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

The Chicago radar (KLOT), 56 km away, was scanning. The volume nearest the touchdown began at 23:28 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

12 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.