Tornadoes · United States · Illinois · 2012

EF0 tornado, Benson to Sparland, Illinois, September 1, 2012

From Benson to Sparland, this EF0 tornado ran 2.3 miles across Woodford and Marshall counties on September 1, 2012, touching down at 12:05 PM CDT and reaching 75 yards wide. It killed nobody, and did $1,000 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.

  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.

The record

Rating
EF0
Date
September 1, 2012
Touchdown
12:05 PM CDT (17:05 UTC)
Lifted
12:09 PM CDT (17:09 UTC)
On the ground
4 minutes
Path length
2.3 miles (3.6 km)
Path width
75 yards (69 m)
Deaths
0
Injuries
0
Property damage
$1,000
Crop damage
$4,000
Counties
Woodford and Marshall counties
Touchdown point
40.904, -89.152
Lift-off point
40.933, -89.171
Record number
1209011105-01

What the Weather Service recorded

The remnants of Hurricane Isaac passed through central Illinois on September 1st, triggering widespread showers and thunderstorms. Due to strong low-level wind shear near a surface boundary stretched across north-central Illinois, many of the storms began to rotate and produce funnel clouds. A total of seven tornadoes touched down across portions of Woodford, Marshall, and Stark counties around midday. Most of the tornadoes were short-lived and did little or no damage.

A tornado briefly touched down in a field about 2 miles east-southeast of Benson in Woodford County at 11:48 AM CDT. No damage was reported.

A tornado touched down in a field about 3 miles north of Benson in Woodford County at 12:03 PM CDT. The tornado traveled west across County Road 2200E before dissipating at 12:04 PM CDT. No damage was reported.

A tornado touched down in a field about 4 miles north-northwest of Benson in Woodford County at 12:05 PM CDT. The tornado traveled northwestward and crossed into Marshall County 1.2 miles southeast of Pattonsburg at 12:08 PM CDT. While in Woodford County, the tornado tore the tin roof off a shed and did minor damage to a corn field.

This tornado formed about 4 miles north-northwest of Benson in Woodford County then crossed into Marshall County 1.2 miles southeast of Pattonsburg at 12:08 PM CDT. The tornado tracked northwestward for 0.5 miles, then dissipated 0.8 miles east-southeast of Pattonsburg at 12:09 PM CDT. No damage was reported.

A tornado briefly touched down on the Illinois River about 1.6 miles south-southeast of Hopewell in Marshall County at 12:32 PM CDT. The tornado dissipated at 12:33 PM CDT. No damage was reported.

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

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), 12:00Z

5.1 hours before the tornado, 98 km from the path. September 1, 2012.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 12:00Z on 2012-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 443 joules per kilogram, CIN 0, lifted condensation level 457 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Lincoln, IL at 12:00Z on 2012-09-01The 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 24 square meters per square second, 0 to 6 km bulk shear 14 knots.1939Sfc1 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
443 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
692 J/kg
Mixed-layer LCL
457 m above ground
0-6 km bulk shear
14 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

Lincoln, IL (KILX), 00:00Z

6.9 hours after it, 98 km from the path. September 2, 2012.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2012-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 220 joules per kilogram, CIN -4, lifted condensation level 482 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Lincoln, IL at 00:00Z on 2012-09-02The 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 79 square meters per square second, 0 to 6 km bulk shear 16 knots.1939Sfc1 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
220 J/kg
Mixed-layer CIN
-4 J/kg
Surface CAPE
405 J/kg
Mixed-layer LCL
482 m above ground
0-6 km bulk shear
16 kt
0-1 km bulk shear
14 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.7 K/km

Open this sounding in Storm Lab

The surface observations

Lacon (C75), 22 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

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

The radar

The Lincoln radar (KILX), 87 km away, was scanning. The volume nearest the touchdown began at 17:04 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.

This ground now

The live radar over the trackEvery 2012 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

The other tornadoes of September 1, 2012

14 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 111:48 AM CDTEF0Woodford, IL0.120
September 112:03 PM CDTEF0Woodford, IL0.720
September 112:32 PM CDTEF0Marshall, IL0.120
September 11:08 PM CDTEF0Stark, IL1.350
September 11:11 PM CDTEF0Stark, IL1.120
September 11:24 PM CDTEF0Stark, IL0.950
September 14:19 PM CDTEF2Clay, AR0.975$5.0 million
September 14:22 PM CDTEF0Clay, AR0.125
September 14:32 PM CDTEF0Butler, MO3.020
September 14:43 PM CDTEF0Butler, MO4.320
September 14:20 PM MDTEF0Cassia, ID1.020
September 14:40 PM MDTEF0Cassia, ID1.020
September 16:41 PM EDTEF0Marion, IN0.125
September 16:03 PM CDTEF0Dunklin, MO0.025$100,000

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.