EF1 tornado, Aledo Mercer Co Arpt to Cable, Illinois, July 12, 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

July 12, 2014

Touchdown

9:30 PM CDT (02:30 UTC)

Lifted

9:40 PM CDT (02:40 UTC)

On the ground

10 minutes

Path length

3.7 miles (6.0 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

Crop damage

$10,000

County

Mercer County

Touchdown point

41.267, -90.667

Lift-off point

41.273, -90.596

Record number

1407122030-01

23 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 104 mph.

• Convergent damage path in corn field. Apparent start of damage path.
• more crop damage.....substantial...chaotic direction.....crosses road
• corn damage....both sides of road
• corn and tree snapped both sides of road. blown down corn

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

A disturbance moving across the region caused a warm front to lift northward across northwest Illinois during the late afternoon and evening. Thunderstorms moving eastward from Iowa produced strong gusty winds that resulted in damage to trees in far northwest Illinois. Farther to the south across Mercer and Henry Counties, a thunderstorm produced a series of 4 tornadoes causing damage to crops, trees, and an outbuilding. Heavy rain also fell along and north of Interstate 80 where 2 to 4 inches was reported.

This EF-0 tornado with peak winds of 75 mph produced damage primarily to corn crops.

This tornado was rated EF-1 with a peak wind of 105 mph. Along its 3.6 mile path, this tornado crossed the roadway in several locations causing damage to crops, power poles and lines as well as to trees. Some branches were 1 to 3 inches in diameter and some tree trunks snapped off.

This tornado was rated EF-1 with peak winds of 100 mph. Along its 2.78 mile path length, this tornado produced mainly crop and tree damage with numerous 1 to 3 inch tree limbs down as well as several large tree trunks snapped off. An outbuilding was also destroyed.

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 tornado watch, issued at 22:00 UTC and running to 03:54 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:52 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.

Moline (MLI), 22 km from the path, in the two hours either side.

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

The Quad Cities radar (KDVN), 38 km away, was scanning. The volume nearest the touchdown began at 02:32 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

5 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.