Tornadoes · United States · Wisconsin · 2022
EF0 tornado, Stockholm, Wisconsin, May 9, 2022
This EF0 tornado ran 1.2 miles across Pepin County on May 9, 2022, touching down at 7:10 PM CDT and reaching 25 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.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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 9, 2022
- Touchdown
- 7:10 PM CDT (00:10 UTC)
- Lifted
- 7:12 PM CDT (00:12 UTC)
- On the ground
- 2 minutes
- Path length
- 1.2 miles (2.0 km)
- Path width
- 25 yards (23 m)
- Deaths
- 0
- Injuries
- 0
- County
- Pepin County
- Touchdown point
- 44.470, -92.252
- Lift-off point
- 44.483, -92.234
- Record number
- 2205091810-01
The damage survey
3 damage points were recorded along this path by NWS MPX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 70 mph.
- Estimated starting point on the Mississippi River based on video evidence.
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 dry-line/cold front that spawn a couple of tornadoes in eastern Minnesota, moved across west central Wisconsin during the evening and produced an additional three tornadoes, plus wind damage, and large hail. The tornadoes occurred near Lake Pepin, near Knapp, and between Colfax and Elk Mound in Dunn County.
The starting point was estimated based on video evidence as it began over the Mississippi River (Lake Pepin). Once onshore, the tornado knocked down or broke about one dozen trees as it moved up the river bluffs and dissipated. Maximum winds were estimated at 70 mph.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
2 minutes of warning. NWS MPX issued a tornado warning for this county at 00:08 UTC, 2 minutes before the tornado touched down, in force until 00:45 UTC.
The county was under a tornado watch, issued at 19:50 UTC and running to 01:52 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 19:50 UTC | 01:52 UTC | Tornado Watch | MPX |
| 23:48 UTC | 00:30 UTC | Severe Thunderstorm Warning | MPX |
| 00:08 UTC | 00:45 UTC | Tornado Warning | MPX |
| 00:22 UTC | 00:45 UTC | Severe Thunderstorm Warning | MPX |
| 00:45 UTC | 01:30 UTC | Severe Thunderstorm Warning | MPX |
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 Enhanced Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 19:58 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.
Minneapolis, MN (KMPX), 00:00Z
0.2 hours before the tornado, 115 km from the path. May 10, 2022.
- Mixed-layer CAPE
- 923 J/kg
- Mixed-layer CIN
- -42 J/kg
- Surface CAPE
- 2090 J/kg
- Mixed-layer LCL
- 1801 m above ground
- 0-6 km bulk shear
- 67 kt
- 0-1 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- -82 m²/s²
- 0-3 km storm-relative helicity
- 66 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.5
- 0-3 km lapse rate
- 8.3 K/km
Minneapolis, MN (KMPX), 12:00Z
11.8 hours after it, 115 km from the path. May 10, 2022.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -98406 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 2428 m above ground
- 0-6 km bulk shear
- 63 kt
- 0-1 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -45 m²/s²
- 0-3 km storm-relative helicity
- 364 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 3.9 K/km
The surface observations
Red Wing (RGK), 23 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 22:15 UTC | 84.2 | 62.6 | 160° 16 kt | 22 | 996.6 | |
| 22:35 UTC | 82.4 | 62.6 | 160° 14 kt | 23 | 996.3 | |
| 22:55 UTC | 84.2 | 62.6 | 170° 14 kt | 20 | 996.6 | VCTS |
| 23:15 UTC | 82.4 | 64.4 | 170° 19 kt | 26 | 996.6 | VCTSRA |
| 23:35 UTC | 80.6 | 66.2 | 170° 13 kt | 20 | 995.6 | -VCTSRA |
| 23:55 UTC | 80.6 | 62.6 | 200° 19 kt | 30 | 997 | -VCTSRA |
| 00:15 UTC | 75.2 | 66.2 | 210° 11 kt | 20 | 998.6 | TSRA |
| 00:35 UTC | 77 | 68 | 320° 4 kt | 999.3 | VCTS | |
| 00:55 UTC | 75.2 | 68 | 110° 4 kt | 999.7 | ||
| 01:15 UTC | 75.2 | 66.2 | 0° 0 kt | 1001.7 | ||
| 01:35 UTC | 78.8 | 53.6 | 310° 9 kt | 1002.4 | ||
| 01:55 UTC | 78.8 | 51.8 | 300° 6 kt | 1002.7 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The La Crosse radar (KARX), 111 km away, was scanning. The volume nearest the touchdown began at 00:11 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 22:50 UTC | HAIL 1 | Prescott | Pierce, WI | FROM SOCIAL MEDIA. |
| 00:10 UTC | TORNADO | 1 Se Stockholm | Pepin, WI | UPDATES PREVIOUS TORNADO REPORT FROM STOCKHOLM. SPOTTER REPORTED TORNADO ON THE MISSISSIPPI RIVER SOUTH OF STOCKHOLM. THE TORNADO WAS ALSO ON VIDEO. ABOUT ONE DOZEN TREES WERE BROKEN AS IT MOVED UP THE BLUFFS EAST OF STO |
| 00:10 UTC | TORNADO | Stockholm | Pepin, WI | SPOTTER REPORTED TORNADO MOVED ACROSS RIVER SOUTH OF STOCKHOLM. TIME ESTIMATED VIA RADAR. |
| 00:25 UTC | TORNADO | 1 E Knapp | Dunn, WI | DOZENS OF TREES WERE BROKEN, INCLUDING AT A HOME EAST OF KNAPP. THE PATH LENGTH WAS 0.7 MILES. THE TORNADO WAS RATED EF0 WITH ESTIMATED MAXIMUM WINDS OF 80 MPH. |
| 00:32 UTC | TORNADO | 3 Ese Cedar Falls | Dunn, WI | UPDATES PREVIOUS TORNADO REPORT FROM 4 E CEDAR FALLS. VIDEO ON TWITTER. NWS SURVEY CONFIRMED TORNADIC DAMAGE JUST NORTH OF I-94 NEAR RUSK, WI. THE DAMAGE CONTINUED TO THE NORTHEAST THROUGH WHITETAIL GOLF COURSE. AN IRRIG |
| 01:06 UTC | HAIL 0.75 | 2 Se Nelson | Buffalo, WI | REPORT FROM MPING: DIME (0.75 IN.). |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2022 tornado in WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin nowThe forecast where you are
The other tornadoes of May 9, 2022
5 more were confirmed in the United States that day.
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.