Tornadoes · United States · Minnesota · 1985

F1 tornado, Jackson County, Minnesota, May 30, 1985

This F1 tornado ran 20.0 miles across Jackson County on May 30, 1985, touching down at 5:50 PM CDT and reaching 400 yards wide. It killed nobody and injured 1, and did $500,000 to $5 million 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
May 30, 1985
Touchdown
5:50 PM CDT (22:50 UTC)
Path length
20.0 miles (32.2 km)
Path width
400 yards (366 m)
Deaths
0
Injuries
1
Property damage
$500,000 to $5 million
County
Jackson County
Touchdown point
43.530, -95.420
Lift-off point
43.680, -95.180
Record number
325

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.

Minneapolis, MN (KSTC), 12:00Z

10.8 hours before the tornado, 194 km from the path. May 30, 1985.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 1985-05-30Temperature 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 -10246, lifted condensation level 942 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, Minneapolis, MN at 12:00Z on 1985-05-30The 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 18 square meters per square second, 0 to 6 km bulk shear 17 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
0 J/kg
Mixed-layer CIN
-10246 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
942 m above ground
0-6 km bulk shear
17 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
2.0 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KSTC), 00:00Z

1.2 hours after it, 194 km from the path. May 31, 1985.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 1985-05-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 187 joules per kilogram, CIN -192, lifted condensation level 1351 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, Minneapolis, MN at 00:00Z on 1985-05-31The 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 191 square meters per square second, 0 to 6 km bulk shear 52 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
187 J/kg
Mixed-layer CIN
-192 J/kg
Surface CAPE
787 J/kg
Mixed-layer LCL
1351 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
191 m²/s²
0-3 km storm-relative helicity
334 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9
0-3 km lapse rate
7.0 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1985 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of May 30, 1985

16 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 302:37 PM CDTF0Gregory, SD0.110
May 302:55 PM CDTF0Wells, ND0.110
May 302:55 PM CDTF2Burleigh, ND0.5100$5,000 to $50,000
May 302:00 PM MDTF0Powder River, MT0.110$500 to $5,000
May 303:12 PM CDTF0Sheridan, ND0.110
May 303:24 PM CDTF0Burleigh, ND0.110
May 304:10 PM CDTF1Brookings, SD4.010$50 to $500
May 305:28 PM CDTF0Grant, MN1.5200$500 to $5,000
May 305:15 PM MDTF0Carter, MT0.110$50 to $500
May 306:25 PM CDTF1Buchanan, MO15.6505$50,000 to $500,000
May 307:28 PM CDTF0Clinton, MO0.250
May 307:38 PM CDTF0Clay, IA0.120
May 3010:22 PM CDTF3Clayton, IA to WI34.01,500227$5 million to $50 million
May 3011:50 PM CDTF2Grant, WI16.0500$50,000 to $500,000
May 3012:20 AM CDTF2Dane, WI21.0100$50,000 to $500,000
May 3012:30 AM CDTF1Barron, WI11.0100$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.