EF1 tornado, Mundelein, Illinois, February 27, 2024

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

EF1

Date

February 27, 2024

Touchdown

7:55 PM CST (01:55 UTC)

Lifted

7:56 PM CST (01:56 UTC)

On the ground

1 minutes

Path length

0.1 miles (0.2 km)

Path width

40 yards (37 m)

Deaths

0

Injuries

1

County

Lake County

Touchdown point

42.262, -87.987

Lift-off point

42.262, -87.985

Record number

2402271955-01

96 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 100 mph.

• 82 mph wind gust at personal weather station.
• Windows broken and fascia stripped. Tree damage at this location as well.
• Fence debris damaged a house.
• Reports of multiple large trees down, estimate 15-20 large pines of 20 to 30 ft and many smaller ones. Relayed via email.

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

Following summer-like, record warmth, severe thunderstorms developed in the late afternoon of February 27th over northwest Illinois and spread east through the evening across the Chicago metro area. A total of 11 tornadoes touched down in Illinois. There were 11 tornadoes in total across the NWS Chicago area of responsibility, which is the most in a February event since official NWS tornado records began in 1950. In addition to the tornadoes, the storms produced numerous instances of severe hail and damaging straight-line wind.

This tornado had a very short path with damage confined primarily to a single two-story apartment building. Most of the roof was removed from the building, and a portion of the brick facade also collapsed when the roof was removed. Two large softwood trees in the parking lot east of the building were uprooted. Debris was deposited to the east across the street, where a few tree branches were also snapped. In the apartment building south of the main one that was damaged, a resident described seeing a second story glass patio door on the east side being pulled out and shattered by the winds. One 13 year old resident sustained bad bruising after part of his ceiling collapsed and struck him in the arm.

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

23 minutes of warning. NWS LOT issued a tornado warning for this county at 01:32 UTC, 23 minutes before the tornado touched down, in force until 02:10 UTC.

The county was under a tornado watch, issued at 21:54 UTC and running to 02:57 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:55 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), 74 km away, was scanning. The volume nearest the touchdown began at 01:52 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 2024 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.