EF0 tornado, Monticello Arpt to Seymour, Illinois, June 7, 2015

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.

Rating

EF0

Date

June 7, 2015

Touchdown

9:03 PM CDT (02:03 UTC)

Lifted

9:07 PM CDT (02:07 UTC)

On the ground

4 minutes

Path length

2.7 miles (4.3 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

Property damage

$85,000

Crop damage

$7,000

Counties

Piatt and Champaign counties

Touchdown point

40.026, -88.490

Lift-off point

40.034, -88.441

Record number

1506072003-01

1 damage points were recorded along this path by NWS ILX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 85 mph.

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

A cold front interacting with a warm and very humid airmass triggered several lines of strong to severe thunderstorms during the afternoon and evening of June 7th. Two brief tornadoes touched down...one in Menard County about 8 miles east of Petersburg and another in Piatt County 4 miles east of Monticello. Numerous reports of wind damage were received, with the city of Peoria being particularly hard hit. 70 to 80 mph winds caused widespread tree and power line damage from Peoria eastward into Pekin. Large hail also occurred with many of the storms, with the largest stones up to the size of golf balls. In addition, heavy rainfall of 3 to 8 inches resulted in extensive flash flooding and numerous road closures in parts of central and southeast Illinois.

A tornado touched down in a field 4.4 miles east of Monticello in Piatt County at 9:03 PM CDT. It then tracked eastward through open farmland before crossing into Champaign County 5.9 miles east of Monticello at 9:05 PM CDT. Minor crop damage was reported.

This tornado crossed from Piatt County into Champaign County 5.5 miles southwest of Seymour at 9:05 PM CDT. It then tracked eastward and hit a farmstead, destroying a barn and a machine shed. Several large trees were also knocked down or damaged at the residence. The tornado then dissipated 5.1 miles south of Seymour at 9:07 PM CDT.

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.

The county was under a severe thunderstorm watch, issued at 00:48 UTC and running to 05:06 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 01:00 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 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.

Champaign - Willard (CMI), 16 km from the path, in the two hours either side.

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

The Lincoln radar (KILX), 75 km away, was scanning. The volume nearest the touchdown began at 02:00 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 2015 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

8 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.