Tornadoes · United States · Minnesota · 1993

F1 tornado, Rock County, Minnesota, June 7, 1993

This F1 tornado ran 12.0 miles across Rock County on June 7, 1993, touching down at 5:52 PM CDT and reaching 200 yards wide. It killed nobody.

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
June 7, 1993
Touchdown
5:52 PM CDT (22:52 UTC)
Path length
12.0 miles (19.3 km)
Path width
200 yards (183 m)
Deaths
0
Injuries
0
County
Rock County
Touchdown point
43.670, -96.230
Lift-off point
43.820, -96.150
Record number
421

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

Issued (UTC)ExpiredProductOffice
22:33 UTC23:15 UTCSevere Thunderstorm WarningFSD
22:59 UTC23:35 UTCTornado WarningFSD

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 High Risk. The outlook in force was issued at 12:04 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.

Aberdeen, SD (KHON), 12:00Z

10.9 hours before the tornado, 218 km from the path. June 7, 1993.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 12:00Z on 1993-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1 joules per kilogram, CIN -478, lifted condensation level 579 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, Aberdeen, SD at 12:00Z on 1993-06-07The 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 372 square meters per square second, 0 to 6 km bulk shear 64 knots.19395878Sfc1 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
1 J/kg
Mixed-layer CIN
-478 J/kg
Surface CAPE
14 J/kg
Mixed-layer LCL
579 m above ground
0-6 km bulk shear
64 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
372 m²/s²
0-3 km storm-relative helicity
509 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5
0-3 km lapse rate
3.2 K/km

Open this sounding in Storm Lab

Aberdeen, SD (KHON), 00:00Z

1.1 hours after it, 218 km from the path. June 8, 1993.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 1993-06-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 206 joules per kilogram, CIN -37, lifted condensation level 1759 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, Aberdeen, SD at 00:00Z on 1993-06-08The 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 -74 square meters per square second, 0 to 6 km bulk shear 82 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
206 J/kg
Mixed-layer CIN
-37 J/kg
Surface CAPE
271 J/kg
Mixed-layer LCL
1759 m above ground
0-6 km bulk shear
82 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
-74 m²/s²
0-3 km storm-relative helicity
9 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1
0-3 km lapse rate
8.2 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1993 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of June 7, 1993

39 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 711:45 AM CDTF0, FL2.0100
June 71:45 PM CDTF1Brule, SD13.0732$50,000 to $500,000
June 71:50 PM CDTF0Buffalo, SD0.130
June 71:55 PM CDTF0Buffalo, SD0.130
June 72:10 PM CDTF1Hughes, SD0.440$500 to $5,000
June 72:46 PM CDTF0Hand, SD0.130
June 72:55 PM CDTF0Hand, SD0.130
June 73:07 PM CDTF0Hand, SD0.130
June 73:30 PM CDTF3Spink, SD5.0400$50,000 to $500,000
June 73:30 PM CDTF2Miner, SD3.073$50,000 to $500,000
June 73:30 PM CDTF2Miner, SD3.073$50,000 to $500,000
June 73:30 PM CDTF2Miner, SD3.073$50,000 to $500,000
June 73:35 PM CDTF2Sanborn, SD9.0100$5,000 to $50,000
June 73:40 PM CDTF2Spink, SD10.0100$50,000 to $500,000
June 73:40 PM CDTF2Spink, SD10.0100$50,000 to $500,000
June 73:40 PM CDTF2Spink, SD10.0100$50,000 to $500,000
June 73:45 PM CDTF1Hanson, SD12.073$5,000 to $50,000
June 73:45 PM CDTF0Sumner, KS0.1100
June 73:54 PM CDTF1McCook, SD5.0100$5,000 to $50,000
June 74:03 PM CDTF0Beadle, SD0.230
June 74:03 PM CDTF1Beadle, SD1.050$5,000 to $50,000
June 74:07 PM CDTF1McCook, SD2.0100$500 to $5,000
June 74:23 PM CDTF3McCook, SD5.0250$5,000 to $50,000
June 74:30 PM CDTF4Minnehaha, SD54.08005$5 million to $50 million
June 74:40 PM CDTF4Lake, SD10.05004$500,000 to $5 million
June 74:50 PM CDTF3Lake, SD6.0100$50,000 to $500,000
June 74:50 PM CDTF3Lake, SD6.0100$50,000 to $500,000
June 76:00 PM CDTF0Deuel, SD0.330$50 to $500
June 76:30 PM CDTF1O'Brien, IA1.867$500 to $5,000
June 76:38 PM CDTF1Sioux, IA7.530$50,000 to $500,000
June 76:40 PM CDTF0O'Brien, IA0.523$500 to $5,000
June 76:41 PM CDTF2Osceola, IA10.01275$5,000 to $50,000
June 76:42 PM CDTF0Sioux, IA0.320$500 to $5,000
June 76:52 PM CDTF1Lyon, MN2.5506$500,000 to $5 million
June 76:57 PM CDTF0Yellow Medicine, MN1.040
June 77:28 PM CDTF1Redwood, MN3.080$50,000 to $500,000
June 77:40 PM CDTF0Jackson, MN0.210
June 79:37 PM CDTF0Green Lake, WI0.123
June 79:45 PM CDTF0Marquette, WI0.123

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.