EF0 tornado, Lake of The Woods, Indiana, July 20, 2018

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.

Rating

EF0

Date

July 20, 2018

Touchdown

1:53 PM EDT (17:53 UTC)

Lifted

1:55 PM EDT (17:55 UTC)

On the ground

2 minutes

Path length

0.5 miles (0.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Marshall County

Touchdown point

41.382, -86.220

Lift-off point

41.387, -86.213

Record number

1807201153-01

4 damage points were recorded along this path by NWS IWX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 75 mph.

• Start of Centerline/Tornado
• Drone view of NW corner of cinder block wall of barn was pushed in several inches. Siding in the area may have been removed. Roof was undamaged.
• Homeowner sent picture of tree top twisted off. Reported it was thrown into a field.

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

Deep low pressure was located over Wisconsin with a warm front extending across northern Indiana. 1000 to 2000 J/KG MLCAPE advected in with area of clearing with effective helicity values in excess of 200 m2/s2. Several strong to severe storms developed with intense microbursts in a few spots as well as a weak tornado.

Drone pictures indicate that a disorganized tornado touched down southwest of the intersection of County Road 6B and Ironwood Road. The NW corner of a barn suffered damage to a cinder block wall. Corn was observed laid down in a semi convergent pattern as the tornado moved northeast across 6B and eventually Ironwood Road where some tree branches were broken along Issac Sells Ditch. The tornado lifted at this point with no further damage noted.

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

1 minute of warning. NWS IWX issued a tornado warning for this county at 17:52 UTC, 1 minute before the tornado touched down, in force until 18:15 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 Enhanced Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:28 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 Northern Indiana radar (KIWX), 43 km away, was scanning. The volume nearest the touchdown began at 17:50 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 2018 tornado in IndianaEvery tornado in Indiana since 1950Warnings in force in Indiana nowThe forecast where you are

9 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.