Tornadoes · United States · Illinois · 2015
EF2 tornado, Delavan, Illinois, July 16, 2015
This EF2 tornado ran 2.4 miles across Tazewell County on July 16, 2015, touching down at 11:39 PM CDT and reaching 250 yards wide. It killed nobody and injured 1, and did $1.2 million of property damage.
The rating scale
Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
EF2111 to 135 mphthis tornado
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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.
The record
- Rating
- EF2
- Date
- July 16, 2015
- Touchdown
- 11:39 PM CDT (04:39 UTC)
- Lifted
- 11:46 PM CDT (04:46 UTC)
- On the ground
- 7 minutes
- Path length
- 2.4 miles (3.8 km)
- Path width
- 250 yards (229 m)
- Deaths
- 0
- Injuries
- 1
- Property damage
- $1.2 million
- Crop damage
- $10,000
- County
- Tazewell County
- Touchdown point
- 40.362, -89.550
- Lift-off point
- 40.379, -89.510
- Record number
- 1507162239-01
The damage survey
55 damage points were recorded along this path by NWS ILX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 120 mph.
- second story removed from house. uninhabitable.
- crop damage a couple hundred yards past cemetery east of Springfield Rd
- tree ripped from ground and tossed in the field in the distance in the photo photo
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
What the Weather Service recorded
A strong cold front interacting with a highly unstable airmass triggered strong to severe thunderstorms across west-central Illinois during the evening of July 16th. Scattered wind damage and flash flooding occurred mainly west of the I-55 corridor. One of the storms produced a short-lived EF-2 tornado that impacted the town of Delavan in Tazewell County, resulting in numerous homes being damaged and two minor injuries.
A tornado touched down 0.6 miles south of Delavan at 11:39 PM CDT. The tornado then moved east-northeast across the south side of Delavan, damaging 51 homes. 15 of the homes sustained severe damage, including either the roofs being completely torn off or the majority of the roof deck being lifted off. Numerous garages, outbuildings, and trees were damaged. The tornado also crossed through the Prairie Rest Cemetery, damaging grave markers and several trees before dissipating in a cornfield 2.2 miles east-northeast of Delavan at 11:46 PM CDT.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
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 22:01 UTC and running to 05:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 14:00 UTC | 06:00 UTC | Flash Flood Watch | ILX |
| 22:01 UTC | 05:00 UTC | Severe Thunderstorm Watch | ILX |
| 02:23 UTC | 03:15 UTC | Severe Thunderstorm Warning | ILX |
| 02:34 UTC | 03:15 UTC | Severe Thunderstorm Warning | ILX |
| 04:40 UTC | 10:45 UTC | Flash Flood Warning | ILX |
| 05:13 UTC | 05:53 UTC | Severe Thunderstorm Warning | ILX |
| 17:00 UTC | 00:00 UTC | Heat Advisory | ILX |
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 forecast that day
The Storm Prediction Center had this point in a Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:49 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 air that afternoon
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.
Lincoln, IL (KILX), 00:00Z
4.7 hours before the tornado, 83 km from the path. July 17, 2015.
- Mixed-layer CAPE
- 836 J/kg
- Mixed-layer CIN
- -23 J/kg
- Surface CAPE
- 2196 J/kg
- Mixed-layer LCL
- 899 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 210 m²/s²
- 0-3 km storm-relative helicity
- 283 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 9.4
- 0-3 km lapse rate
- 5.5 K/km
Lincoln, IL (KILX), 12:00Z
7.3 hours after it, 83 km from the path. July 17, 2015.
- Mixed-layer CAPE
- 2277 J/kg
- Mixed-layer CIN
- -132 J/kg
- Surface CAPE
- 3314 J/kg
- Mixed-layer LCL
- 1052 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 65 m²/s²
- 0-3 km storm-relative helicity
- 89 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.8
- 0-3 km lapse rate
- 4.8 K/km
The surface observations
Lincoln (AAA), 29 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 02:55 UTC | 79.7 | 73.4 | 170° 7 kt | 1009.8 | ||
| 03:15 UTC | 79.16 | 73.4 | 160° 7 kt | 1010.2 | ||
| 03:35 UTC | 79 | 73.76 | 180° 7 kt | 1009.8 | VCTS | |
| 03:55 UTC | 79.16 | 74 | 190° 8 kt | 1009.1 | VCTS | |
| 04:15 UTC | 79.7 | 74.3 | 10° 7 kt | 1010.5 | TS | |
| 04:35 UTC | 79 | 72.68 | 140° 4 kt | 1010.5 | VCTS | |
| 04:55 UTC | 78.62 | 73.4 | 120° 4 kt | 1010.5 | VCTS | |
| 05:15 UTC | 77 | 72.68 | 140° 5 kt | 1010.2 | TS | |
| 05:35 UTC | 77.54 | 73.58 | 170° 5 kt | 1010.2 | VCTS | |
| 05:55 UTC | 78 | 73.58 | 10° 8 kt | 1011.2 | VCTS | |
| 06:15 UTC | 79.7 | 73.58 | 160° 6 kt | 1010.5 | ||
| 06:35 UTC | 79.7 | 74 | 180° 7 kt | 1010.5 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Lincoln radar (KILX), 29 km away, was scanning. The volume nearest the touchdown began at 04:41 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.
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 01:57 UTC | TSTM WND DMG | 1 N Norris | Fulton, IL | CORN BLOWN OVER |
| 01:57 UTC | TSTM WND GST 80 | 1 N Norris | Fulton, IL | |
| 02:15 UTC | TSTM WND GST 70 | 5 Sw Peoria | Peoria, IL | FROM PEORIA CO. EOC |
| 04:20 UTC | HEAVY RAIN 1.37 | 4 Ene East Peoria | Tazewell, IL | |
| 04:37 UTC | FUNNEL CLOUD | Delavan | Tazewell, IL | FUNNEL CLOUD REPORTED BY TRAINED SPOTTERS AND SAN JOSE FIRE DEPT. RELAYED BY LOGAN CO. DISPATCH. CORRECTED TIME. |
| 04:37 UTC | TORNADO 2 | Delavan | Tazewell, IL | PATH LENGTH 1.3 MILES...WIDTH 250 YARDS. TOUCHED DOWN 0.8 MILES SOUTH OF DELAVAN AND LIFTED 1.1 MILES EAST-SOUTHEAST OF DELAVAN. 51 HOMES DAMAGED...15 SEVERELY. MOST SEVERELY DAMAGED HOMES HAD THE ROOF TORN OFF OR A MAJO |
| 04:37 UTC | TORNADO | Delavan | Tazewell, IL | NUMEROUS STRUCTURES HEAVILY DAMAGED ON THE SOUTHEAST SIDE OF TOWN. |
| 04:40 UTC | FUNNEL CLOUD | Delavan | Tazewell, IL | FUNNEL CLOUD REPORTED BY TRAINED SPOTTERS AND SAN JOSE FIRE DEPT. RELAYED BY LOGAN CO. DISPATCH. |
| 04:40 UTC | TORNADO | Delavan | Tazewell, IL | |
| 05:20 UTC | HEAVY RAIN 4 | 4 Nw Hopedale | Tazewell, IL | |
| 05:25 UTC | TSTM WND DMG | Armington | Tazewell, IL | SEVERAL TREES DOWN IN TOWN...SOME BLOCKING ROADWAYS. TIME ESTIMATED FROM RADAR. |
| 05:28 UTC | TSTM WND DMG | 4 Nw Atlanta | Logan, IL | DELAYED REPORT. SEVERAL LARGE TREE BRANCHES DOWN AND TIN ROOF BLOWN OFF OUTBUILDING. TIME ESTIMATED. |
| 06:15 UTC | HEAVY RAIN 4.5 | Hopedale | Tazewell, IL | 4.50 INCHES OF RAIN REPORTED IN HOPEDALE |
| 06:15 UTC | HEAVY RAIN 6 | Hopedale | Tazewell, IL | 5 TO 6 INCHES OF RAIN REPORTED IN HOPEDALE |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2015 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are
The other tornadoes of July 16, 2015
8 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| July 16 | 5:14 PM CDT | EF0 | Henry, IA | 1.5 | 10 | |||
| July 16 | 6:09 PM CDT | EF1 | Henderson, IL | 0.8 | 100 | $25,000 | ||
| July 16 | 6:49 PM CDT | EF1 | Warren, IL | 1.4 | 50 | $2,000 | ||
| July 16 | 7:00 PM CDT | EF1 | Rock Island, IL | 1.1 | 200 | $2,000 | ||
| July 16 | 7:09 PM CDT | EF2 | Warren, IL | 1.7 | 300 | $150,000 | ||
| July 16 | 7:13 PM CDT | EF2 | Warren, IL | 6.0 | 700 | 1 | $1.5 million | |
| July 16 | 8:34 PM CDT | EF0 | Mitchell, IA | 2.1 | 40 | $40,000 | ||
| July 16 | 8:48 PM CDT | EF0 | Whiteside, IL | 0.6 | 10 |
What this means
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.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.