EF0 tornado, Rea to Grape, Michigan, April 1, 2023

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

April 1, 2023

Touchdown

11:03 AM EDT (15:03 UTC)

Lifted

11:08 AM EDT (15:08 UTC)

On the ground

5 minutes

Path length

7.1 miles (11.5 km)

Path width

75 yards (69 m)

Deaths

0

Injuries

0

Property damage

$25,000

County

Monroe County

Touchdown point

41.946, -83.711

Lift-off point

41.966, -83.575

Record number

2304010903-01

5 damage points were recorded along this path by NWS DTX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 80 mph.

• Significant shingle damage to house near the intersection of Petersburg Rd and Brewer Rd.
• Roof partially blown off, windows blown out, and car damage in downtown Dundee - specifically around Memorial Park. Suspect funneling effects between buildings locally increased wind speeds in this area.
• Sporadic large limbs downed in the area of Sullivan Rd and Dixon Rd.
• Stand of pine trees downed near the intersection of Petersburg Rd and Brewer Rd.

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

A disorganized area of showers and some embedded thunderstorms tracked into southeast Michigan during the late morning hours of April 1st, 2023. While the overall environment was marginal owing to lack of instability, locally favorable conditions for severe weather developed south of I-94 as upper and low level features briefly interacted. The thunderstorm complex reinvigorated between 10 and 11 AM, eventually becoming severe for a brief period over Lenawee/Monroe/southern Wayne Counties. These storms produced damaging wind gusts, sub-severe hail (spotters reported up to M&M size), and a brief/weak EF-0 tornado in Dundee. The tornado was on the ground for 5 minutes, causing damage consistent with 80 MPH wind gusts as it tracked through the heart of downtown Dundee. By noon, storms had shifted into Canada and the severe weather threat was over.

The tornado touched down at the intersection of Brewer Rd and Petersburg Rd west southwest of Dundee. Damage in this area included a stand of pine trees down, damage to an outbuilding, and some significant shingle damage to a house with winds estimated at 75 mph in strength. The tornado then tracked along Brewer Rd with damage consisting of sporadic downed large limbs as Brewer Rd turned into Riley St. upon entering into the village of Dundee. Estimated wind speeds increased to a peak of 80 mph in downtown Dundee...specifically in the immediate vicinity of Memorial Park...with increased wind speeds aided by funneling effects between downtown buildings. Damage in this area consisted of a roof being partially blown off, windows blown out, downed limbs, and nearby car damage. The tornado then tracked further east northeastward until ending near the intersection of Dixon Rd and Sullivan Rd with continued sporadic downed large limbs.

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.

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 General Thunderstorms Risk. The outlook in force was issued at 12:44 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.

Monroe (TTF), 17 km from the path, in the two hours either side.

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

The Detroit radar (KDTX), 84 km away, was scanning. The volume nearest the touchdown began at 15:03 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 2023 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are

21 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.