Tornadoes · United States · Minnesota · 2024

EF0 tornado, Hayfield, Minnesota, May 20, 2024

This EF0 tornado ran 1.4 miles across Dodge County on May 20, 2024, touching down at 6:25 PM CDT and reaching 35 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 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.

The record

Rating
EF0
Date
May 20, 2024
Touchdown
6:25 PM CDT (23:25 UTC)
Lifted
6:28 PM CDT (23:28 UTC)
On the ground
3 minutes
Path length
1.4 miles (2.2 km)
Path width
35 yards (32 m)
Deaths
0
Injuries
0
County
Dodge County
Touchdown point
43.955, -92.956
Lift-off point
43.944, -92.932
Record number
2405201725-01

What the Weather Service recorded

On May 20th, isolated severe thunderstorms produced large hail up to half dollar size across southeast Minnesota. Additionally, two brief landspout tornadoes occurred in Dodge county during the evening hours.

Brief touchdown in open field. Witnessed by multiple sources and path documented via satellite imagery.

Brief touchdown in open field. Witnessed by multiple sources and path documented via satellite imagery.

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

What forecasters said that day

The local office's own words before the tornado touched down, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS La Crosse, WI wrote its last area forecast discussion before the tornado touched down at May 20, 6:15 PM CDT, 10 minutes earlier.

Area forecast discussion, May 20, 6:15 PM CDT, 10 minutes before
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Hazardous weather outlook, May 20, 1:32 PM CDT, 4 hours 53 minutes before
Hazardous Weather Outlook
National Weather Service La Crosse WI
132 PM CDT Mon May 20 2024

IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-211200-
Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-
Clayton-Wabasha-Dodge-Olmsted-Winona-Mower-Fillmore-Houston-
Taylor-Clark-Buffalo-Trempealeau-Jackson-La Crosse-Monroe-Juneau-
Adams-Vernon-Crawford-Richland-Grant-
132 PM CDT Mon May 20 2024

This Hazardous Weather Outlook is for parts of southeast
Minnesota...northeast Iowa and southwest into central Wisconsin.

.DAY ONE...Tonight

Storms will redevelop, especially across parts of southeast
Minnesota and northern Iowa. Strong to severe storms could develop
overnight with large hail and damaging winds.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Multiple rounds of storms are expected Tuesday. Storms could
impact the area Tuesday morning, with more redevelopment expected
Tuesday afternoon and evening / 3-9pm / when the highest
potential for severe storms exists. Storm activity later in the
day will depend on where morning storms track. All hazards are
possible Tuesday with damaging wind gusts and tornadoes being the
primary threats, large hail is also possible with some storms.

With the consecutive rounds of thunderstorms, localized areas may
recieve several inches of rain. As a result, the threat for river
rises and flooding will be on the increase. Those with interests
along area creeks, streams, and rivers should monitor conditions
closer to start the week.

More thunderstorms are possible later in the week / Friday and
Saturday / but it is too early to discern the severe weather
threat at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters should monitor the weather closely tonight through
Tuesday. Tuesday afternoon and evening look like the highest
potential for severe weather but please report any hail, gusty
winds, or other severe weather if observed. Activation could be
needed at times.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

Naylor/Shea

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.

Minneapolis, MN (KMPX), 12:00Z

11.4 hours before the tornado, 113 km from the path. May 20, 2024.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2024-05-20Temperature 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 -88729, lifted condensation level 685 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, Minneapolis, MN at 12:00Z on 2024-05-20The 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 52 square meters per square second, 0 to 6 km bulk shear 32 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
-88729 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
685 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

0.6 hours after it, 113 km from the path. May 21, 2024.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2024-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1078 joules per kilogram, CIN -12, lifted condensation level 1148 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, Minneapolis, MN at 00:00Z on 2024-05-21The 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 43 square meters per square second, 0 to 6 km bulk shear 35 knots.193958Sfc1 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
1078 J/kg
Mixed-layer CIN
-12 J/kg
Surface CAPE
2009 J/kg
Mixed-layer LCL
1148 m above ground
0-6 km bulk shear
35 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
149 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.4
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The surface observations

Dodge Center (TOB), 12 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

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

The radar

The Minneapolis radar (KMPX), 112 km away, was scanning. The volume nearest the touchdown began at 23:26 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.

This ground now

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

The other tornadoes of May 20, 2024

2 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 206:10 PM CDTEF0Dodge, MN1.250
May 208:18 PM CDTUnratedShelby, IA0.420

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.