EF1 tornado, Mott Muni Arpt, North Dakota, June 21, 2016

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

June 21, 2016

Touchdown

8:10 PM MDT (02:10 UTC)

Lifted

8:20 PM MDT (02:20 UTC)

On the ground

10 minutes

Path length

3.2 miles (5.1 km)

Path width

35 yards (32 m)

Deaths

0

Injuries

0

Property damage

$200,000

Crop damage

$30,000

County

Hettinger County

Touchdown point

46.310, -102.402

Lift-off point

46.324, -102.339

Record number

1606212010-01

4 damage points were recorded along this path by NWS BIS, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 105 mph.

• Worst damage along tornado path. Garage torn from home. Half of the roof removed.

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

A compact upper level low approached North Dakota while strong instability and very strong deep layer shear were present over a broad portion of the state. Storms initiated over eastern Montana into southwest North Dakota and moved across the area in the evening and overnight hours. Storms were slow to intensify at first, then around 730 pm CDT explosive growth occurred over western North Dakota. Strong supercells developed producing very large hail along with funnel clouds. There were two confirmed tornadoes. One caused damage to a home south of Mott in Hettinger County, while the other occurred over rural areas between Arnegard and Watford City in McKenzie County. Severe storms continued overnight with the threat switching to primarily strong winds over south central North Dakota where there were multiple reports of damage. The greatest damage was in Logan County where a high-voltage electrical transmission structure was toppled.

A tornado moved from southwest of Mott towards the east-northeast for just over three miles. Initial damage was to large cottonwood trees at a farmstead, along with light damage to the home. About half-way through the tornado path, another home was severely damaged. The entire attached three stall garage was destroyed and half the roof was torn from the home. Windows were broken and vehicles were damaged. Debris was strewn through nearby fields for one mile. No injuries or fatalities occurred, as the occupants of both homes took shelter.

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

2 minutes of warning. NWS BIS issued a tornado warning for this county at 02:08 UTC, 2 minutes before the tornado touched down, in force until 02:45 UTC.

The county was under a severe thunderstorm watch, issued at 01:37 UTC and running to 03:42 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, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 01:45 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), 133 km away, was scanning. The volume nearest the touchdown began at 02:10 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 2016 tornado in North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are

4 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.