EF1 tornado, Riga, Michigan, June 20, 2021

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

June 20, 2021

Touchdown

9:23 PM EDT (01:23 UTC)

Lifted

9:27 PM EDT (01:27 UTC)

On the ground

4 minutes

Path length

2.7 miles (4.3 km)

Path width

125 yards (114 m)

Deaths

0

Injuries

0

Property damage

$250,000

County

Lenawee County

Touchdown point

41.814, -83.836

Lift-off point

41.829, -83.788

Record number

2106201923-01

19 damage points were recorded along this path by NWS DTX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 90 mph.

• Barn wall collapsed, side barn collapsed, siding damage, blown out windows, and small sheet metal silo blown apart with sections carried over quarter mile downstream.
• Chimney toppled, multiple large hardwoods snapped, large hardwood uprooted, sheet metal debris speared through fence post.
• Three wood transmission poles toppled and/or snapped one with street light.
• Large tree uprooted and fell crushing fence.

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

Severe thunderstorms, mainly south of the M-59 corridor (and especially south of I-94) began during the evening hours of June 20, 2021 and extending into the early morning hours of June 21, 2021. Numerous reports of wind damage were received, with multiple trees down in the hardest hit areas of Lenawee, Monroe, Wayne, and portions of Oakland counties. The damaging winds of 60+ mph, resulted in at least 60,000 customers losing power across portions of southeast Michigan. The severe thunderstorms occurred south of a stationary boundary draped near the I-94 corridor, with a moist and unstable boundary to the south of it across far southern Lower Michigan into the northern Ohio Valley.||In addition to the numerous wind reports, the first tornado of 2021 occurred in Riga Township, located in far southeast Lenawee county. This was the first tornado in southeast Michigan since September 2019 in Sanilac county. The Riga tornado was rated EF-1 with estimated peak winds of 90 mph and a path length just shy of 3 miles. The tornado was the first in Lenawee county since an EF-1 tornado that occurred northwest of Adrian back on June 6, 2010.

A tornado touched down south of Cemetery Rd and east of Silberhorn Hwy heading east-northeast. The tornado damaged at least five homes, four outbuildings, three barns, and numerous trees. Damage included a mix of uprooted trees, snapped large limbs, roof loss, collapsed barn walls, fallen power poles, a toppled chimney, blown out fencing, and an overturned air conditioner unit. Large sections of sheet metal from a destroyed small sheet metal silo were also lofted over a quarter mile downstream. The tornado inflicted damage on a final metal barn roof |as it neared the Lenawee/Monroe county line then lifted prior to |Rodesiler Hwy between Simpson and Stadler Rd. Estimated peak winds was 90 mph.

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.

The county was under a severe thunderstorm watch, issued at 22:09 UTC and running to 05:00 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 01:25 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.

Lambertville (DUH), 16 km from the path, in the two hours either side.

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

The Detroit radar (KDTX), 102 km away, was scanning. The volume nearest the touchdown began at 01:22 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 2021 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are

7 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.