EF1 tornado, Walker to Romeoville, Illinois, June 30, 2014

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

June 30, 2014

Touchdown

9:55 PM CDT (02:55 UTC)

Lifted

9:58 PM CDT (02:58 UTC)

On the ground

3 minutes

Path length

3.1 miles (4.9 km)

Path width

75 yards (69 m)

Deaths

0

Injuries

0

Property damage

$500,000

County

Will County

Touchdown point

41.627, -88.185

Lift-off point

41.624, -88.126

Record number

1406302055-01

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 95 mph.

• Siding on east side of house peeled back to the south.
• Dead tree uprooted generally to the east.
• Most branches broken from tree.
• Numerous large branches downed.

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

Extensive damage was sustained from two separate lines of thunderstorms on Monday, June 30th which was officially determined to be from two separate derecho events from Central Iowa east into Michigan and Ohio. Thunderstorms developed over Iowa during the early afternoon and organized into a forward-propagating quasi-linear convective system (QLCS) and tracked to southern Lake Michigan by early to mid evening. Meanwhile, a second complex of intense thunderstorms developed over central and eastern Iowa and also evolved into a QLCS, tracking across northern Illinois and northwest Indiana late in the evening into the overnight hours. ||Across northern Illinois and northwest Indiana, the first derecho event produced scattered straight-line wind damage, with gusts measured as high as 70 MPH. The second derecho produced far more extensive damage, with 80 to 90 MPH straight line winds and numerous tornadoes. Initial post-event surveys cataloged 18 tornadoes across northern Illinois and northwest Indiana, 17 of EF1 intensity and one of EF0 intensity. Of these 18 tornadoes, 14 were associated with a pair of large mesovortices that traveled along the Kankakee River Valley in Kankakee County, Illinois and Lake, Newton, and Jasper Counties in Indiana. ||Analysis of Google Earth satellite imagery gathered in spring of 2015 showed numerous additional areas of damage not documented in the original survey efforts. A thorough analysis of this imagery and synthesis with the original survey information led to a complete reanalysis of the Kankakee Valley tornadoes. Ultimately, 18 tornado tracks were identified alone in the Kankakee Valley, leading to a total of 22 tornadoes for northern Illinois and northwest Indiana. Of the 18 revised tornadoes, 16 of the paths were determined, in part, using satellite imagery. Further re-examination of the damage also led to a change in rating for several of the damage locations. Of the 18 reanalyzed Kankakee Valley tracks, two were rated EF2, 13 were rated EF1, and three were rated EF0. Additional details on this reanalysis, including the methods used, can be found in the Electronic Journal of Severe Storms Meteorology (Lyza et al. 2019, ���A Multi-Platform Reanalysis of the Kankakee Valley Tornado Cluster on 30 June 2014���).

A tornado caused damage to trees and residences between Plainfield and Romeoville. Over 50 trees, including many large softwood trees, were uprooted within a concentrated path. A dozen modest to large trees were blown to the northwest against the eastward path of the storm. Numerous roads were blocked due to fallen trees. There was minor damage to numerous residences in the Woodlands of the Reserve and Lakewood Falls subdivisions. This damage was mainly siding and shingles peeled off along with windows blown out. The tornado crossed I-55 near mile marker 261. The tornado was embedded within a larger area of straight line wind damage. Maximum winds were estimated to 95 mph.

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 02:01 UTC and running to 03:59 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 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.

The Chicago radar (KLOT), 6 km away, was scanning. The volume nearest the touchdown began at 02:53 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 2014 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

45 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.