Tornadoes · United States · Illinois · 2015

EF1 tornado, Fulton to Fairhaven, Illinois, April 9, 2015

From Fulton to Fairhaven, this EF1 tornado ran 8.3 miles across Carroll and Whiteside counties on April 9, 2015, touching down at 6:02 PM CDT and reaching 50 yards wide. It killed nobody.

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.

  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.

The record

Rating
EF1
Date
April 9, 2015
Touchdown
6:02 PM CDT (23:02 UTC)
Lifted
6:15 PM CDT (23:15 UTC)
On the ground
13 minutes
Path length
8.3 miles (13.4 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Counties
Carroll and Whiteside counties
Touchdown point
41.923, -90.076
Lift-off point
41.976, -89.931
Record number
1504091702-01

The damage survey

38 damage points were recorded along this path by NWS DVN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 107 mph.

  • Debris trail to the northeast
  • Storage rental buildings lifted and destroyed.
  • irrigator flipped. Debris in trees on bluff
  • Outbuilding (possibly open to the west) lifted and blown into power lines across the road.

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 powerful storm system lifted from Central Iowa into northern Illinois and southern Wisconsin during the day on April 9th. Strong to severe thunderstorms developed in eastern Iowa during the afternoon and moved into northwest Illinois during the evening hours. These storms produced hail as large as golf balls, damaging winds of 60 to 70 mph, and two tornadoes. The tornadoes touched down near Fulton and Thomson Illinois. Both tornadoes produced EF-1 damage to mainly trees and farm outbuildings.

A NWS Storm Survey found that a tornado touched downed 1 mile southeast of the Clinton County Airport, tracked through the north side of Clinton, IA moved into Whiteside County. It was on the ground for 3.91 miles in Whiteside County before it lifted about 5 miles northeast of Fulton. The primary damage was to farm outbuildings, a storage shed and damage to trees.

A NWS Storm Survey found that a tornado touched down 5 miles northeast of Fulton Illinois and lifted 8 miles east of Thomson Illinois. The tornado was on the ground for 1.08 miles in Whiteside Counties. The damage was primarily to trees and farm outbuildings.

A NWS Storm Survey found that a tornado touched down 5 miles northeast of Fulton Illinois and lifted 8 miles east of Thomson Illinois. The tornado was on the ground for 7.22 miles in Carroll County caused damage primarily to trees and farm outbuildings.

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

The warnings

13 minutes of warning. NWS DVN issued a tornado warning for this county at 22:49 UTC, 13 minutes before the tornado touched down, in force until 23:15 UTC.

The county was under a tornado watch, issued at 18:00 UTC and running to 00:21 UTC.

Issued (UTC)ExpiredProductOffice
18:00 UTC00:21 UTCTornado WatchDVN
22:49 UTC23:15 UTCTornado WarningDVN

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 Enhanced Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 20:00 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 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.

Davenport, (KDVN), 12:00Z

11.0 hours before the tornado, 55 km from the path. April 9, 2015.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2015-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 101 joules per kilogram, CIN -154, lifted condensation level 614 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 12:00Z on 2015-04-09The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 323 square meters per square second, 0 to 6 km bulk shear 55 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
101 J/kg
Mixed-layer CIN
-154 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
614 m above ground
0-6 km bulk shear
55 kt
0-1 km bulk shear
45 kt
0-1 km storm-relative helicity
323 m²/s²
0-3 km storm-relative helicity
253 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4
0-3 km lapse rate
2.4 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 00:00Z

1.0 hours after it, 55 km from the path. April 10, 2015.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2015-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 338 joules per kilogram, CIN -52, lifted condensation level 1114 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 00:00Z on 2015-04-10The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 104 square meters per square second, 0 to 6 km bulk shear 66 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
338 J/kg
Mixed-layer CIN
-52 J/kg
Surface CAPE
375 J/kg
Mixed-layer LCL
1114 m above ground
0-6 km bulk shear
66 kt
0-1 km bulk shear
53 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.4
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

The surface observations

Savanna (SFY), 14 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:15 UTC6454.3250° 6 kt998.6VCTS
21:35 UTC64.7655.2250° 6 kt998.3
21:55 UTC64.5856.1260° 8 kt997.6
22:15 UTC6556.6660° 4 kt997.3VCTS
22:35 UTC65.8457.38120° 3 kt997.3TS
22:55 UTC65.358360° 5 kt997+TSRA
23:15 UTC61.759240° 10 kt17997.3+TSRA
23:35 UTC6360.62200° 3 kt997-VCTSRA
23:55 UTC65.6658.82210° 9 kt996.6VCTS
00:15 UTC65.4856.48230° 9 kt995.9VCTS
00:35 UTC64.2256.3270° 5 kt995.9
00:55 UTC6356.3230° 7 kt995.9

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

The radar

The Quad Cities radar (KDVN), 61 km away, was scanning. The volume nearest the touchdown began at 23:03 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)ReportWhereCountyRemark
23:23 UTCHAIL 12 Se DixonLee, IL
23:28 UTCHAIL 1.752 Se DixonLee, ILHAIL NOW TO GOLF BALL SIZE.
23:32 UTCHAIL 1.751 N Franklin GroveLee, ILDAYSDILLE ROAD AND NAYLOR
23:36 UTCHAIL 1.751 N Franklin GroveLee, IL
23:38 UTCHAIL 1.755 N Franklin GroveOgle, IL
23:39 UTCTORNADO1 Nne Franklin GroveLee, IL*** 2 FATAL, 2 INJ *** RATING: EF-4 ESTIMATED PEAK WIND: 200 MPH PATH LENGTH /STATUTE/: 30.2 MILES PATH WIDTH /MAXIMUM/: 700 YARDS START DATE:APRIL 09 2015 START TIME:6:39 PM CDT START LOCATION:0.9 MILES NE FRANKLIN GROV
23:40 UTCTORNADO2 Ne Franklin GroveLee, ILVIEWED FROM I-88. DEBRIS SEEN.
23:40 UTCTORNADOAshtonLee, ILREPORT OF DAMAGE AND INJURIES AT THE KRAFT FOOD WAREHOUSE NEAR ASHTON. TIME ESTIMATED FROM RADAR.
23:45 UTCTSTM WND DMG1 Se FreeportStephenson, IL10 INCH DIAMETER LIMB BLOWN DOWN IN FREEPORT. TIME ESTIMATED.
23:45 UTCHAIL 1.752 E Mount MorrisOgle, IL

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 April 9, 2015

18 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 91:32 PM CDTEF0Peoria, IL0.110
April 95:04 PM CDTEF1Scott, IA22.4100$20,000
April 96:22 PM EDTEF0Hillsdale, MI0.670
April 95:40 PM CDTEF1Clinton, IA to IL12.575
April 96:37 PM CDTEF0Boone, IL2.825
April 96:38 PM CDTEF2Cherokee, TX1.8340$300,000
April 96:39 PM CDTEF4Rochelle–Fairdale tornado, IL30.1700211$19 million
April 97:05 PM CDTEF0Ogle, IL1.9100
April 97:10 PM CDTEF1Gregg, TX1.3335$1.0 million
April 97:15 PM CDTEF1Boone, IL4.0100$80,000
April 97:20 PM CDTEF1Harrison, TX4.5760$300,000
April 97:24 PM CDTEF0Boone, IL0.430$20,000
April 97:25 PM CDTEF1Boone, IL3.950$150,000
April 97:47 PM CDTEF0Christian, IL0.110
April 97:50 PM CDTEF1McHenry, IL0.330
April 99:08 PM CDTEF0Custer, OK0.230
April 99:16 PM CDTEF0Cape Girardeau, MO1.8150$6,000
April 99:31 PM CDTEF0Cape Girardeau, MO1.7130$60,000

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.