EF1 tornado, Warsaw to Little Chicago, Minnesota, May 19, 2021

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

May 19, 2021

Touchdown

8:17 PM CDT (01:17 UTC)

Lifted

8:21 PM CDT (01:21 UTC)

On the ground

4 minutes

Path length

1.2 miles (1.9 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

County

Rice County

Touchdown point

44.433, -93.311

Lift-off point

44.450, -93.312

Record number

2105191917-01

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

• Apparent start of tornado based on spotter video.
• A few branches were downed at the apparent end of the tornado. No tree damage was noted farther north.
• Tornado was over an open field at this point per storm chaser video
• A number of trees were uprooted, some of which were lofted a couple hundred feet per video.

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

There were several low-topped supercells that developed along a warm front across Southern Minnesota Wednesday evening, May 19, 2021. These storms produced 7 short-lived tornadoes and several funnel clouds across southern Minnesota. These tornadoes were weak and most rated EF0. This was a marginal CAPE, marginal wind shear environment with low cloud bases. A strengthening low-level jet led to an increase in low-level wind shear. This was able to produce a few low-topped supercells that were efficient tornado producers.

Trained spotters took video of a tornado that touched down in an open field and moved northward. It struck a farmstead at the end of its path, with only large branches knocked down per a NWS damage survey.

Two storm chasers took video of a narrow tornado. A damage survey revealed that several trees were broken or blown down. Law enforcement and spotters were also watching the tornado.

A storm chaser took video of a tornado moving in an open field and then along a line of trees. Some of the trees were uprooted and lofted a couple hundred feet in the air. A NWS damage survey also noted uprooted trees.

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

12 minutes of warning. NWS MPX issued a tornado warning for this county at 01:05 UTC, 12 minutes before the tornado touched down, in force until 01:45 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 Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 01:03 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.

Faribault Municipal (FBL), 13 km from the path, in the two hours either side.

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

The Minneapolis radar (KMPX), 50 km away, was scanning. The volume nearest the touchdown began at 01:18 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 2021 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

8 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.