EF1 tornado, German Corner to Atkinson, Illinois, May 14, 2020

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

May 14, 2020

Touchdown

10:16 PM CDT (03:16 UTC)

Lifted

10:20 PM CDT (03:20 UTC)

On the ground

4 minutes

Path length

4.3 miles (6.9 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

County

Henry County

Touchdown point

41.318, -90.076

Lift-off point

41.367, -90.026

Record number

2005142116-01

5 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 110 mph.

• A 70 foot concrete silo was nearly completely destroyed. Two small horse sheds were destroyed. A storage shed was damaged, and the trunk of a tree was snapped.
• Portions of a feeder canopy removed and lofted.

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

Showers and thunderstorms tracked across central Iowa into eastern Iowa, northeast Missouri, and northwest Illinois late Friday afternoon and into the overnight hours. These storms brought heavy rain, frequent lightning, damaging winds, and large hail to the region. The hardest hit areas were Keokuk county in Iowa, towards Henry county in Iowa, where 50-70 mph winds occurred. A weak EF-1 tornado occurred near Atkinson, IL in Henry county in Illinois after 1015 pm and caused damage to trees and outbuildings at two farmsteads. ||Widespread rainfall amounts over 1 inch generally fell south of a line from Sigourney and Maquoketa, IA to Freeport, IL. This rainfall combined with the previous days rain brought rain totals of 2-4 inches to the area.

An EF1 tornado moved through rural Henry County, Illinois last Thursday night, May 14th. The tornado began around 10:16 pm CDT, and caused significant damage at a farmstead, with estimated maximum winds of 110 mph. The tornado nearly completely destroyed a 70 foot concrete silo, snapped the trunk of a large tree, completely destroyed two horse sheds, and damaged an equipment shed. The tornado then moved rapidly northeast along an intermittent four and a quarter mile path, and caused tree and outbuilding damage at two other farmsteads. The tornado lifted around 10:20 pm CDT. Times and begin/end locations were estimated by radar. Field assistance by the Henry County Emergency Manager and OEM volunteers to complete the remote survey is greatly appreciated.

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 23:18 UTC and running to 04:47 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 Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 00:51 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 Quad Cities radar (KDVN), 53 km away, was scanning. The volume nearest the touchdown began at 03:15 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 2020 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.