F1 tornado, Ralph to Gwinn, Michigan, June 10, 2000

1. F040 to 72 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. F173 to 112 mphthis tornado

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. F2113 to 157 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. F3158 to 206 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. F4207 to 260 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. F5261 to 318 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

F1

Date

June 10, 2000

Touchdown

3:20 PM CDT (20:20 UTC)

Path length

7.5 miles (12.1 km)

Path width

300 yards (274 m)

Deaths

0

Injuries

0

Counties

Dickinson and Marquette counties

Touchdown point

46.170, -87.730

Lift-off point

46.180, -87.570

Record number

968

A sharp temperature contrast between a warm, very moist airmass behind an east-west warm front across central Upper Michigan and cool air near Lake Superior helped fuel thunderstorms the afternoon of June 10th. Modest instability combined with the high moisture content of the atmosphere and surface dew points above 70 degrees F produced severe weather. A low topped supercell formed along the warm front and was responsible for spawning an F1 tornado. The tornado touched down in the Escanaba State Forest in northeast Dickinson County and tracked from west to east on a nearly continuous 7 1/2 mile path through the woods into southern Marquette County. Michigan Department of Natural Resources (DNR) aerial photography showed the path varying from about 200 feet to 1200 feet wide, becoming very narrow and evidencing skipping during its last 1 1/2 miles of travel. The tornado track began in Dickinson County T44 R28W S13 and ended in Marquette County T44 R26W S18. Michigan DNR GPS-derived end points of the tornado track are (deg.min.sec) 46.12.31N/87.45.4W and 46.12.63N/87.31.16W. The Michigan DNR estimates 400 acres of downed timber at a value of 250K. The DNR expects to be able to harvest and recover about half the timber.

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.

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 19:58 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.

Gwinn/Sawyer Afb (SAW), 28 km from the path, in the two hours either side.

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

The Marquette radar (KMQT), 40 km away, was scanning. The volume nearest the touchdown began at 20:20 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.

The live radar over the trackEvery 2000 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan 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.