Unrated tornado, Wilton, North Dakota, August 1, 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 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. Unratedthis tornado

   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

Unrated

Date

August 1, 2023

Touchdown

9:04 PM CDT (02:04 UTC)

Lifted

9:07 PM CDT (02:07 UTC)

On the ground

3 minutes

Path length

0.4 miles (0.7 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Burleigh County

Touchdown point

47.150, -100.810

Lift-off point

47.144, -100.806

Record number

2308012004-01

A short wave trough moved through the region while its affiliated surface boundary moved from southern Saskatchewan and northeast Montana into northwest North Dakota, and continued to move towards the southeast. Thunderstorms along this line intensified greatly as it settled to the southeast into an environment of elevated instability and deep layer shear, with multiple areas of severe weather developing. Well ahead of the line, another distinct area of severe weather developed where storms initiated along various outflow boundaries, particularly when two boundaries intersected. These storms were northerly moving. Eventually, the fontal boundary settled far enough south that all storms became focused along it. Many storms became very intense, especially a long-lived supercell thunderstorm that originally became severe near central Williams County before moving southeast and remaining severe all the way to northern Burleigh County. The most intense damage from this storm was in the Beulah Bay and Hazen Bay areas of northern Mercer County, where parts of roofs were torn off homes, large trees were uprooted, manufactured homes were severely damaged, and some campers and boats were flipped. Winds were estimated to be up to 95 mph. In addition, crops were severely damaged over a widespread area, with many fields flattened and determined to be a total loss. Along with the large hail and severe wind gusts with this episode, there was one tornado near Wilton in Burleigh County. No damage was reported with the tornado and so by National Weather Service policy the tornado is rated EF Unknown.

The tornado touched down in an open field southwest of Wilton and impacted no structures. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

The county was under a severe thunderstorm watch, issued at 20:52 UTC and running to 05:00 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 Slight Risk. The outlook in force was issued at 00:59 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.

The Bismarck radar (KBIS), 42 km away, was scanning. The volume nearest the touchdown began at 02:03 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 North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are

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.