Tornadoes · United States · Wisconsin · 2024

EF1 tornado, Detroit Harbor to Washington Island, Wisconsin, May 21, 2024

From Detroit Harbor to Washington Island, this EF1 tornado ran 2.3 miles across Door County on May 21, 2024, touching down at 10:32 PM CDT and reaching 50 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  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.

The record

Rating
EF1
Date
May 21, 2024
Touchdown
10:32 PM CDT (03:32 UTC)
Lifted
10:34 PM CDT (03:34 UTC)
On the ground
2 minutes
Path length
2.3 miles (3.7 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Door County
Touchdown point
45.349, -86.915
Lift-off point
45.382, -86.904
Record number
2405212132-01

The damage survey

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

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

What the Weather Service recorded

A line of thunderstorms developed ahead of a cold front during the early evening on Tuesday (5/21) and tracked through much of northeast Wisconsin through the rest of the evening. Straight line winds produced wind damage along with 5 tornadoes.

A tornado formed at 10:32 pm CDT on the southern part of Washington Island in northern Door County and continued northeast before dissipating at 10:34 pm CDT in the central part of Washington Island. Total path length is estimated to be 2.28 miles long, with a width of 50 yards. Peak wind estimated to be around 90 mph.

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

The warnings

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 tornado watch, issued at 23:43 UTC and running to 04:48 UTC.

Issued (UTC)ExpiredProductOffice
23:43 UTC04:48 UTCTornado WatchGRB
02:21 UTC03:00 UTCSevere Thunderstorm WarningGRB
02:59 UTC03:45 UTCSevere Thunderstorm WarningGRB
14:42 UTC21:00 UTCBeach Hazard StatementGRB

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 forecast that day

The Storm Prediction Center had this point in a Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 01:11 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 air that afternoon

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.

Green Bay/Straub, WI (KGRB), 00:00Z

3.5 hours before the tornado, 136 km from the path. May 22, 2024.

Skew-T log-pSkew-T log-p diagram, Green Bay/Straub, WI at 00:00Z on 2024-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 442 joules per kilogram, CIN -98, lifted condensation level 1016 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Green Bay/Straub, WI at 00:00Z on 2024-05-22The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 49 square meters per square second, 0 to 6 km bulk shear 57 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
442 J/kg
Mixed-layer CIN
-98 J/kg
Surface CAPE
232 J/kg
Mixed-layer LCL
1016 m above ground
0-6 km bulk shear
57 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
149 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

Green Bay/Straub, WI (KGRB), 12:00Z

8.5 hours after it, 136 km from the path. May 22, 2024.

Skew-T log-pSkew-T log-p diagram, Green Bay/Straub, WI at 12:00Z on 2024-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -98567, lifted condensation level 616 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Green Bay/Straub, WI at 12:00Z on 2024-05-22The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 106 square meters per square second, 0 to 6 km bulk shear 34 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-98567 J/kg
Surface CAPE
404 J/kg
Mixed-layer LCL
616 m above ground
0-6 km bulk shear
34 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.6 K/km

Open this sounding in Storm Lab

The radar

The Green Bay radar (KGRB), 135 km away, was scanning. The volume nearest the touchdown began at 03:33 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
03:05 UTCTSTM WND DMG2 W Egg HarborDoor, WITree down blocking Bay Shore Drive near Horseshoe Bay. Time estimated based on radar.
03:05 UTCTSTM WND DMG2 W Egg HarborDoor, WITree down blocking Bay Shore Drive near Horseshoe Bay. Time estimated based on radar.
03:10 UTCTSTM WND DMGEgg HarborDoor, WITrees and wires down.
03:10 UTCTSTM WND DMGEgg HarborDoor, WITrees and wires down.
03:11 UTCTSTM WND DMGFish CreekDoor, WITrees down.
03:11 UTCTSTM WND DMGFish CreekDoor, WITrees down.
03:32 UTCTORNADO2 Ssw Washington IslandDoor, WINWS Green Bay Damage Survey, with coordination from Door County Emergency Management, found an EF-1 tornado that started at this location and went NE for 2.28 miles. Estimated Peak Wind was 90 mph. Delayed Report.
03:35 UTCTSTM WND DMG2 Ssw Washington IslandDoor, WITrees down with home damage. Multiple additional trees with roads blocked in the area.
03:35 UTCTSTM WND DMG2 Ssw Washington IslandDoor, WITrees down with home damage. Multiple additional trees with roads blocked in the area.
03:35 UTCTSTM WND DMG2 Sw Washington IslandDoor, WIMultiple trees and wires down across Washington Island. Officials are starting to clear roads.
03:35 UTCTSTM WND DMG2 Sw Washington IslandDoor, WIMultiple trees and wires down across Washington Island. Officials are starting to clear roads.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2024 tornado in WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin nowThe forecast where you are

The other tornadoes of May 21, 2024

42 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 214:54 AM CDTEF0Polk, NE4.175$1.0 million
May 215:14 AM CDTEF0Colfax, NE0.550
May 215:23 AM CDTEF0Butler, NE0.650
May 215:27 AM CDTEF0Butler, NE2.650
May 215:45 AM CDTEF0Saunders, NE0.450
May 217:10 AM CDTEF0Montgomery, IA0.740
May 217:32 AM CDTEF1Page, IA3.380
May 2112:52 PM CDTEF0Saunders, NE0.250
May 212:30 PM CDTEF1Buena Vista, IA1.675
May 212:35 PM CDTEF1Montgomery, IA2.970
May 212:43 PM CDTEF3Page, IA33.91,300$1.0 million
May 212:57 PM CDTEF1Page, IA1.785
May 212:59 PM CDTEF4Greenfield tornado, IA40.61,600535$32 million
May 213:09 PM CDTEF0Audubon, IA7.2100$10,000
May 213:18 PM CDTEF1Adams, IA12.7200$101,000
May 213:39 PM CDTEF2Adair, IA14.6200$750,000
May 213:48 PM CDTEF0Martin, MN2.375
May 213:50 PM CDTEF0Union, IA4.075$20,000
May 214:25 PM CDTEF0Warren, IA1.040$30,000
May 214:28 PM CDTEF0Warren, IA2.075$10,000
May 214:30 PM CDTEF2Polk, IA40.81,0004$8.4 million
May 215:25 PM CDTEF0Henry, MO0.350
May 215:27 PM CDTEF1Rogers, OK5.3500$100,000
May 215:39 PM CDTEF1Rogers, OK1.0100$10,000
May 215:41 PM CDTEF0Goodhue, MN0.725
May 216:01 PM CDTEF1Winona, MN to WI19.7110$320,000
May 216:14 PM CDTEF1Buffalo, WI3.9100$80,000
May 216:17 PM CDTEF1Buffalo, WI2.745$126,000
May 216:34 PM CDTEF1Trempealeau, WI0.8150$79,000
May 216:56 PM CDTEF1Eau Claire, WI9.5440
May 216:59 PM CDTEF1Jackson, WI3.175
May 217:08 PM CDTEF1Clark, WI7.0300$140,000
May 217:20 PM CDTEF1Clark, WI9.1120$88,000
May 217:27 PM CDTEF1Clark, WI4.0150$270,000
May 217:29 PM CDTEF1Clark, WI2.275$70,000
May 217:33 PM CDTEF0Clark, WI1.475$33,000
May 217:34 PM CDTEF1Clark, WI4.0110$345,000
May 217:47 PM CDTEF1Marathon, WI2.160
May 217:49 PM CDTEF1Dane, WI4.675$1.1 million
May 217:51 PM CDTEF1Marathon, WI2.180
May 217:59 PM CDTEF1Marquette, WI5.360$60,000
May 218:58 PM CDTEF1Outagamie, WI2.780

What this means

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.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.