Tornadoes · United States · Michigan · 1994

F1 tornado, West Branch, Michigan, July 6, 1994

This F1 tornado ran 0.1 miles across Ogemaw County on July 6, 1994, touching down at 5:20 PM EDT and reaching 50 yards wide. It killed nobody, and did $500 to $5,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  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.

The record

Rating
F1
Date
July 6, 1994
Touchdown
5:20 PM EDT (21:20 UTC)
Path length
0.1 miles (0.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$500 to $5,000
County
Ogemaw County
Touchdown point
44.180, -84.280
Record number
718

What the Weather Service recorded

Tornado touched down at the Ron Deneau residence on the south side of Greenwood Road one-half mile west of M-30 in southeast Edwards Township. The tornado touched down momentarily, 18 feet from the residence, and carried away a 16-foot aluminum boat, a lawnmower, and a 10 X 12 feet aluminum storage shed/workshop and all contents. The residence sustained only minor damage on the north side, apparently from inflow field winds picking up small gravel from the edge of Greenwood Road and firing it through the vinyl siding of the residence. Only small portions of the shed were found spread across a field extending 0.3 mile east-southeast. Heavy hand tools from the shed were found along highway M-30, 0.6 mile east-southeast, on the far side of a one-quarter mile wide stand of mature, 60 to 70-foot high hardwoods. The boat, lawnmower, and remainder of shed and contents remain missing.

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

The air that afternoon

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.

Detroit, MI (KFNT), 12:00Z

9.3 hours before the tornado, 176 km from the path. July 6, 1994.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 12:00Z on 1994-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1873 joules per kilogram, CIN -118, lifted condensation level 1033 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Detroit, MI at 12:00Z on 1994-07-06The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 46 square meters per square second, 0 to 6 km bulk shear 26 knots.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
1873 J/kg
Mixed-layer CIN
-118 J/kg
Surface CAPE
1497 J/kg
Mixed-layer LCL
1033 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
31 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.2
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

Detroit, MI (KFNT), 00:00Z

2.7 hours after it, 176 km from the path. July 7, 1994.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 00:00Z on 1994-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3396 joules per kilogram, CIN -2, lifted condensation level 1060 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Detroit, MI at 00:00Z on 1994-07-07The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 22 square meters per square second, 0 to 6 km bulk shear 25 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
3396 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
3765 J/kg
Mixed-layer LCL
1060 m above ground
0-6 km bulk shear
25 kt
0-1 km bulk shear
5 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
51 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.6
0-3 km lapse rate
7.4 K/km

Open this sounding in Storm Lab

The surface observations

Houghton Lake (HTL), 37 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

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

This ground now

The live radar over the trackEvery 1994 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are

The other tornadoes of July 6, 1994

12 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 62:30 PM CDTF1Cerro Gordo, IA11.530$50,000 to $500,000
July 62:50 PM MDTF0Dewey, SD0.110$5,000 to $50,000
July 64:43 PM CDTF0Fayette, IA0.220$50 to $500
July 64:50 PM CDTF0Allamakee, IA0.120
July 64:20 PM MDTF0Grant, NE0.523
July 65:00 PM MDTF2Morrill, NE6.01501$500,000 to $5 million
July 66:30 PM CDTF0Hughes, SD0.110
July 65:50 PM MDTF1Sioux, NE2.033$5,000 to $50,000
July 66:50 PM CDTF0Green Lake, WI0.123$50 to $500
July 66:17 PM MDTF0Stanley, SD0.110
July 67:45 PM CDTF0Green Lake, WI0.123$50 to $500
July 67:50 PM CDTF1Green Lake, WI1.050$500 to $5,000

What this means

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.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.