Tornadoes · United States · Michigan · 1965

F4 tornado, Branch, Hillsdale, Lenawee and Monroe counties, Michigan, April 11, 1965

This F4 tornado ran 80.5 miles across Branch, Hillsdale, Lenawee and Monroe counties on April 11, 1965, touching down at 7:40 PM GMT-5 and reaching 10 yards wide. It killed 21 people and injured 293.

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 mph

    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 mphthis tornado

    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
F4
Date
April 11, 1965
Touchdown
7:40 PM GMT-5 (00:40 UTC)
Path length
80.5 miles (129.5 km)
Path width
10 yards (9 m)
Deaths
21
Injuries
293
Counties
Branch, Hillsdale, Lenawee and Monroe counties
Touchdown point
41.800, -85.000
Lift-off point
42.080, -83.470
Record number
155

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), 00:00Z

0.7 hours before the tornado, 109 km from the path. April 12, 1965.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 00:00Z on 1965-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 177 joules per kilogram, CIN -85, lifted condensation level 1257 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 00:00Z on 1965-04-12The 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 164 square meters per square second, 0 to 6 km bulk shear 88 knots.1939587897117Sfc1 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
177 J/kg
Mixed-layer CIN
-85 J/kg
Surface CAPE
315 J/kg
Mixed-layer LCL
1257 m above ground
0-6 km bulk shear
88 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
164 m²/s²
0-3 km storm-relative helicity
375 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.6
0-3 km lapse rate
6.6 K/km

Open this sounding in Storm Lab

Detroit, MI (KFNT), 12:00Z

11.3 hours after it, 109 km from the path. April 12, 1965.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 12:00Z on 1965-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -18605, lifted condensation level 719 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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 1965-04-12The 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 68 square meters per square second, 0 to 6 km bulk shear 27 knots.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
-18605 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
719 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
21 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
-53 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.4 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1965 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are

The other tornadoes of April 11, 1965

44 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 113:30 AM GMT-6F2Muskogee, OK0.110$500 to $5,000
April 1112:55 PM GMT-6F4Cedar, IA91.520013$500,000 to $5 million
April 111:15 PM GMT-6F1Chickasaw, IA49.9300$50,000 to $500,000
April 112:00 PM GMT-6F1Green, WI27.116740$500,000 to $5 million
April 112:30 PM GMT-6F2Jefferson, WI14.51,320328$500,000 to $5 million
April 112:45 PM GMT-6F1Crawford, WI13.310$5,000 to $50,000
April 113:20 PM GMT-6F4Crystal Lake tornado, IL9.1400675
April 113:50 PM GMT-6F2Lake, IL4.5200$50,000 to $500,000
April 113:50 PM GMT-6F1Walworth, WI1.950$50,000 to $500,000
April 113:55 PM GMT-6F1Walworth, WI1.010$5,000 to $50,000
April 114:00 PM GMT-6F1Kane, IL0.3150$50,000 to $500,000
April 114:04 PM GMT-6F1Lake, IL0.5250$50,000 to $500,000
April 114:14 PM GMT-6F1Monroe, WI2.050$5,000 to $50,000
April 114:45 PM GMT-6F3Starke, IN35.62501082$5 million to $50 million
April 115:54 PM GMT-5F4Ottawa, MI20.63005142$500,000 to $5 million
April 115:10 PM GMT-6F3Porter, IN33.110$5 million to $50 million
April 116:15 PM GMT-5F4Dunlap tornado, IN21.21031252
April 116:40 PM GMT-5F4Midway tornado, IN21.6177541$50,000 to $500,000
April 116:00 PM GMT-6F4Hillsdale tornado, Indiana and Michigan90.31,76023294$50 million to $500 million
April 117:05 PM GMT-5F1Allegan, MI19.520019$50,000 to $500,000
April 117:07 PM GMT-5F4Tippecanoe, IN21.850044
April 117:10 PM GMT-5F4Twin Lakes tornado, IN37.033336321
April 117:20 PM GMT-5F4Russiaville–Kokomo–Marion tornado, IN48.088025835$50 million to $500 million
April 117:30 PM GMT-5F3Kalamazoo, MI14.215017$50,000 to $500,000
April 117:40 PM GMT-5F3Barry, MI14.1105$50,000 to $500,000
April 117:50 PM GMT-5F4Lebanon–Sheridan tornado, IN45.71,66728123$5 million to $50 million
April 117:10 PM GMT-6F4Berne tornado, Indiana and Ohio52.5104125$5 million to $50 million
April 118:15 PM GMT-5F4Clinton, MI21.010018$50,000 to $500,000
April 118:25 PM GMT-5F2Montcalm, MI15.14401$50,000 to $500,000
April 118:30 PM GMT-5F2Gratiot, MI0.150$5,000 to $50,000
April 118:30 PM GMT-5F2Gratiot, MI0.550$5,000 to $50,000
April 118:30 PM GMT-5F2Gratiot, MI1.050$5,000 to $50,000
April 118:50 PM GMT-5F2Bay, MI9.9102$50,000 to $500,000
April 119:00 PM GMT-5F2Tuscola, MI9.010$50,000 to $500,000
April 118:30 PM GMT-6F4Toledo tornado, Ohio and Michigan5.620018236$5 million to $50 million
April 119:30 PM GMT-5F4Cairo tornado, OH32.540013104$500,000 to $5 million
April 1110:00 PM GMT-5F4Fort Loramie tornado, OH18.4300350$500,000 to $5 million
April 1110:15 PM GMT-5F3Seneca, OH15.0300430$50,000 to $500,000
April 1111:05 PM GMT-5F4Grafton–Strongsville tornado, OH22.040018200$5 million to $50 million
April 1111:15 PM GMT-5F1Preble, OH0.110$5,000 to $50,000
April 1111:30 PM GMT-5F1Medina, OH8.22006$50,000 to $500,000
April 1111:30 PM GMT-5F2Union, OH22.2400462$500,000 to $5 million
April 1111:50 PM GMT-5F1Greene, OH0.110$5,000 to $50,000
April 1112:30 AM GMT-5F1Pickaway, OH38.430013$50,000 to $500,000

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.