EF0 tornado, Lankin to Whitman, North Dakota, August 13, 2007

1. EF065 to 85 mphthis tornado

   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. 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

EF0

Date

August 13, 2007

Touchdown

2:38 PM CDT (19:38 UTC)

Lifted

2:48 PM CDT (19:48 UTC)

On the ground

10 minutes

Path length

6.0 miles (9.7 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

Counties

Nelson and Walsh counties

Touchdown point

48.237, -98.221

Lift-off point

48.150, -98.055

Record number

0708131338-01

On the morning of the 13th, one large supercell tracked across southwest Benson County (ND) and western Eddy County (ND). This storm tracked southeast toward northern Barnes County (ND), then weakened as it moved into Cass County (ND). A second large supercell then developed in Towner County (ND) and tracked toward Thompson, ND. As the second storm moved into southeast Grand Forks County (ND), additional storms developed to the east along and just south of the U.S. Highway 2 corridor in Minnesota. As the second supercell moved across eastern Ramsey and northern Nelson Counties (in ND), it displayed a classic hook echo on radar.

The tornado tracked intermittently to the southeast, from about 3 miles northwest of Whitman to the Nelson County line about 2.5 miles north-northwest of Whitman. The tornado continued to the southeast into Nelson County, where it dissipated at 148 pm CST. The total tornado track was about 6 miles, with about 1 mile of that total occurring in Walsh County. The portion of the tornado track in Walsh County was mainly across wetlands. Peak wind speeds were estimated at 80 mph.

This tornado originated in Walsh County at 138 pm CST, and it crossed into Nelson County about 140 pm CST. The total tornado track was about 6 miles, and about 5 miles of the total occurred in Nelson County. The tornado broke down several trees in shelterbelts and swirled crop swathes in its path. Peak wind speeds were estimated at 80 mph.

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

5 minutes of warning. NWS FGF issued a tornado warning for this county at 19:33 UTC, 5 minutes before the tornado touched down, in force until 20:11 UTC.

The county was under a severe thunderstorm watch, issued at 14:49 UTC and running to 19:57 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 16:31 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 Fargo/Grand Forks radar (KMVX), 96 km away, was scanning. The volume nearest the touchdown began at 19:37 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 2007 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.