EF1 tornado, Bowman Arpt to Ludlow, North Dakota, June 30, 2015

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 30, 2015

Touchdown

8:24 PM CDT (01:24 UTC)

Lifted

8:34 PM CDT (01:34 UTC)

On the ground

10 minutes

Path length

3.9 miles (6.2 km)

Path width

80 yards (73 m)

Deaths

0

Injuries

0

Property damage

$165,000

Crop damage

$75,000

Counties

Bowman and Harding counties

Touchdown point

45.980, -103.420

Lift-off point

45.929, -103.388

Record number

1506301924-02

A Surface trough and associated frontal boundary extended across southeast Montana into southwest North Dakota. The initial thunderstorms formed over eastern Montana and moved into west central North Dakota. The majority of damage was done by four distinct storms.

A long-lived supercell thunderstorm tracked southeast from North Dakota across far northwestern South Dakota during the evening. The storm produced large hail, wind gusts to 80 mph, and a tornado in far northern Harding County near the North Dakota border.

This tornado crossed the state line from Bowman County, North Dakota, into Harding County, South Dakota, in the National Weather Service Rapid City County Warning Area.||The total path length of the tornado was nearly four miles. In Bowman County it was on the ground for a little more than two and a half miles and in Harding County for about a mile and a quarter.||In North Dakota the tornado did damage on a farm near 45.96 north latitude and 103.41 west longitude, about one mile north of the county and state line. On that farm outbuildings and fences were damaged and trees were uprooted. The farm house had shingles torn from the roof. Also, 21 wooden power poles were damaged to varying degree. The tornado damage corresponded to higher end EF1 and from that wind speeds were estimated to be around 105 mph. In South Dakota the tornado impacted no structures and for that segment it was rated EF0, with lower wind speeds. The overall tornado is rated EF1.||See StormData entries for this tornado from Harding County.

A tornado touched down in southern Bowman County, North Dakota and moved south into South Dakota west of US Highway 85. The total path length was almost four miles, and was on the ground over a mile in South Dakota. It caused no damage in Harding County, but did damage buildings on a farm about a mile north of the state line estimated around 100 mph and corresponding to EF1. Additional information on the first portion of this tornado is in the North Dakota, Central and West section of this Storm Data report.

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 tornado watch, issued at 22:32 UTC and running to 04:44 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 01:01 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.

Buffalo (2WX), 40 km from the path, in the two hours either side.

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

The Rapid City radar (KUDX), 208 km away, was scanning. The volume nearest the touchdown began at 01:23 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 2015 tornado in North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are

3 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.