EF1 tornado, Hanerville to Utica, Wisconsin, March 31, 2023

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

March 31, 2023

Touchdown

7:49 PM CDT (00:49 UTC)

Lifted

7:59 PM CDT (00:59 UTC)

On the ground

10 minutes

Path length

4.8 miles (7.6 km)

Path width

75 yards (69 m)

Deaths

0

Injuries

0

Property damage

$100,000

County

Dane County

Touchdown point

42.874, -89.168

Lift-off point

42.937, -89.130

Record number

2303311849-01

19 damage points were recorded along this path by NWS MKX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 100 mph.

• Large portion of partially rotted tree downed.
• Start of Cambridge/Lake Ripley EF0 Tornado.
• End of Green County Tornado 3.
• End of Cambridge/Lake Ripley EF0 Tornado.

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

A warm front was draped across southern Wisconsin on the evening of March 31st which had numerous thunderstorms develop along it. Most of the stronger storms that interacted with the warm front ended up producing some brief EF-0 to EF-1 tornadic damage. There were a few incidents that looked to be from straight line winds along the southeast side of the rotations, but most of the damage appeared to be lofted and from tornadoes.

Tornado damage path tracked from southeast of Stoughton and ended up by Washington Rd east of the city. Mainly tree damage noted along the path, though there were some farm outbuildings that had roofing damage along with some powerlines being snapped near Tower Drive.

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

14 minutes of warning. NWS MKX issued a tornado warning for this county at 00:35 UTC, 14 minutes before the tornado touched down, in force until 01:15 UTC.

The county was under a tornado watch, issued at 19:36 UTC and running to 01:24 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 19:54 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.

Madison (MSN), 31 km from the path, in the two hours either side.

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

The Milwaukee radar (KMKX), 49 km away, was scanning. The volume nearest the touchdown began at 00:49 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 WisconsinEvery tornado in Wisconsin since 1950Warnings in force in Wisconsin nowThe forecast where you are

126 more were confirmed in the United States that day.

All 127 of them

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.