Tornadoes · United States · Michigan · 1997

F1 tornado, Montrose, Michigan, July 2, 1997

This F1 tornado ran 0.3 miles across Genesee County on July 2, 1997, touching down at 4:20 PM EDT and reaching 73 yards wide. It killed nobody, and did $50,000 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 2, 1997
Touchdown
4:20 PM EDT (20:20 UTC)
Path length
0.3 miles (0.5 km)
Path width
73 yards (67 m)
Deaths
0
Injuries
0
Property damage
$50,000
County
Genesee County
Touchdown point
43.250, -83.900
Lift-off point
43.250, -83.900
Record number
839

The warnings

5 minutes of warning. NWS DTX issued a tornado warning for this county at 20:15 UTC, 5 minutes before the tornado touched down, in force until 20:45 UTC.

Issued (UTC)ExpiredProductOffice
19:05 UTC19:45 UTCTornado WarningDTX
19:46 UTC20:15 UTCTornado WarningDTX
20:15 UTC20:45 UTCTornado WarningDTX

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 forecast that day

The Storm Prediction Center had this point in a Moderate Risk. The outlook in force was issued at 05:44 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 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 (KDTX), 12:00Z

8.3 hours before the tornado, 70 km from the path. July 2, 1997.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 12:00Z on 1997-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 103 joules per kilogram, CIN -131, lifted condensation level 1006 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 1997-07-02The 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 119 square meters per square second, 0 to 6 km bulk shear 32 knots.1939587897Sfc1 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
103 J/kg
Mixed-layer CIN
-131 J/kg
Surface CAPE
34 J/kg
Mixed-layer LCL
1006 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
119 m²/s²
0-3 km storm-relative helicity
140 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7
0-3 km lapse rate
3.9 K/km

Open this sounding in Storm Lab

Detroit, MI (KDTX), 00:00Z

3.7 hours after it, 70 km from the path. July 3, 1997.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 00:00Z on 1997-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 673 joules per kilogram, CIN -102, lifted condensation level 877 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km-30°-20°-10°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 1997-07-03The 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 152 square meters per square second, 0 to 6 km bulk shear 30 knots.193958Sfc1 km3 km6 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
673 J/kg
Mixed-layer CIN
-102 J/kg
Surface CAPE
347 J/kg
Mixed-layer LCL
877 m above ground
0-6 km bulk shear
30 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
152 m²/s²
0-3 km storm-relative helicity
171 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.3
0-3 km lapse rate
5.2 K/km

Open this sounding in Storm Lab

The surface observations

Flint (FNT), 34 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
18:54 UTC8973180° 14 kt221002
19:54 UTC8473170° 16 kt241000
20:20 UTC84.273.4180° 16 kt241000
20:37 UTC80.673.4210° 14 kt24999.3
20:44 UTC78.875.2220° 13 kt201000.7
20:54 UTC7674230° 17 kt221000.3+TSRA BR
21:12 UTC71.669.8220° 13 kt1001.7
21:14 UTC69.869.8210° 14 kt1001.7
21:22 UTC71.669.8220° 7 kt191001.4
21:25 UTC71.669.8250° 7 kt191001
21:54 UTC7471160° 11 kt1000.3

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

This ground now

The live radar over the trackEvery 1997 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are

The other tornadoes of July 2, 1997

23 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 21:30 PM CDTF0, FL0.210$2,000
July 23:00 PM EDTF1Crawford, MI13.0150
July 23:41 PM EDTF1Saginaw, MI2.060$400,000
July 23:50 PM EDTF1Saginaw, MI0.343$400,000
July 24:10 PM EDTF1Saginaw, MI2.060$200,000
July 23:12 PM ESTF0Hamilton, IN0.573$10,000
July 24:15 PM EDTF1Arenac, MI3.01501
July 24:20 PM EDTF1Genesee, MI2.060
July 24:20 PM EDTF1Saginaw, MI1.543
July 24:30 PM EDTF3Genesee, MI2.01,000$600,000
July 23:40 PM ESTF2Madison, IN5.0110$600,000
July 24:41 PM EDTF1Livingston, MI10.030$200,000
July 24:45 PM EDTF3Genesee, MI1.71,50011$3.8 million
July 24:04 PM ESTF0Henry, IN0.150$1,000
July 25:15 PM EDTF1Lapeer, MI1.01,000$200,000
July 25:32 PM EDTF1Oakland, MI0.3231$2.0 million
July 23:55 PM MDTF0Gallatin, MT0.120
July 26:00 PM EDTF2Wayne, MI5.02,50090$90 million
July 26:13 PM EDTF0Macomb, MI0.71006$30 million
July 24:18 PM MDTF0Gallatin, MT0.120
July 26:30 PM EDTF0Franklin, OH0.2100$30,000
July 27:00 PM EDTF2Greene, OH0.2300$50,000
July 28:30 PM EDTF3Clermont, OH12.0500$2.0 million

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.