Tornadoes · United States · Minnesota · 2005

F1 tornado, Rothsay, Minnesota, August 25, 2005

This F1 tornado ran 0.3 miles across Wilkin County on August 25, 2005, touching down at 5:49 PM CDT and reaching 50 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
August 25, 2005
Touchdown
5:49 PM CDT (22:49 UTC)
Path length
0.3 miles (0.5 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Wilkin County
Touchdown point
46.430, -96.280
Lift-off point
46.430, -96.280
Record number
1102

What the Weather Service recorded

A torrnado briefly touched down and tracked eastward for about one-quarter of a mile across the north edge of a farmstead. Numerous trees were snapped off or uprooted. A 12x48 foot mobile home was flipped onto its top and destroyed. The mobile home had been resting on its transport wheels in an east-west orientation and was not anchored. It was flipped about 25 yards to the northeast and landed in a north-south orientation. Peak winds were estimated at 110 mph.

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

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
22:36 UTC23:30 UTCSevere Thunderstorm WarningFGF
22:59 UTC00:00 UTCTornado WarningFGF
23:59 UTC01:00 UTCSevere Thunderstorm WarningFGF
00:55 UTC01:56 UTCSevere Thunderstorm WarningFGF

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 General Thunderstorms Risk. The outlook in force was issued at 19:59 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 (KABR), 12:00Z

10.8 hours before the tornado, 237 km from the path. August 25, 2005.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 12:00Z on 2005-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1435 joules per kilogram, CIN -185, lifted condensation level 511 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, Aberdeen, SD at 12:00Z on 2005-08-25The 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 41 square meters per square second, 0 to 6 km bulk shear 28 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
1435 J/kg
Mixed-layer CIN
-185 J/kg
Surface CAPE
807 J/kg
Mixed-layer LCL
511 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
5 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

Aberdeen, SD (KABR), 00:00Z

1.2 hours after it, 237 km from the path. August 26, 2005.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 2005-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 317 joules per kilogram, CIN -257, lifted condensation level 782 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, Aberdeen, SD at 00:00Z on 2005-08-26The 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 40 square meters per square second, 0 to 6 km bulk shear 44 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
317 J/kg
Mixed-layer CIN
-257 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
782 m above ground
0-6 km bulk shear
44 kt
0-1 km bulk shear
24 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.4
0-3 km lapse rate
4.1 K/km

Open this sounding in Storm Lab

The radar

The Fargo/Grand Forks radar (KMVX), 146 km away, was scanning. The volume nearest the touchdown began at 22:48 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
22:00 UTCHAIL 17 N BrushvaleWilkin, MN
22:50 UTCTSTM WND DMG5 S RothsayWilkin, MN10 INCH DIAMETER TREE DOWN ACROSS ROAD BLOCKING TRAFFIC FOR A FEW HOURS. NUMEROUS SMALLER BRANCHES AND TREES DOWN.
22:50 UTCTSTM WND DMG5 Sse RothsayOtter Tail, MN10 INCH DIAMETER TREE DOWN ACROSS ROAD BLOCKING TRAFFIC FOR A FEW HOURS. NUMEROUS SMALLER BRANCHES AND TREES DOWN.
22:50 UTCHAIL 1.56 Wnw ElizabethOtter Tail, MNSTORM REPORT WAS ALONG WILKIN AND OTTER TAIL COUNTY LINE.
22:50 UTCHAIL 1.752 S RothsayWilkin, MN
22:50 UTCHAIL 1.755 S RothsayWilkin, MN
22:50 UTCHAIL 1.755 Sse RothsayOtter Tail, MN
22:52 UTCTSTM WND GST 903 S RothsayWilkin, MNGRAIN BINS TIPPED OVER AND MANY LARGE TREES DOWN IN AKRON TOWNSHIP, SECTION 13.
22:55 UTCTSTM WND DMG6 Wnw ElizabethOtter Tail, MN10 INCH DIAMETER TREE DOWN ACROSS ROAD AND GRAIN BINS HEAVILY DAMAGED.
22:55 UTCTSTM WND GST 581 Nw RothsayWilkin, MNMINNESOTA DOT RWIS EQUIPMENT
22:55 UTCTSTM WND GST 906 Wnw ElizabethOtter Tail, MN10 INCH DIAMETER TREE DOWN ACROSS ROAD AND GRAIN BINS HEAVILY DAMAGED.
23:00 UTCTSTM WND DMGCarlisleOtter Tail, MNTRAILER OVERTURNED ALONG INTERSTATE 94
23:00 UTCFLASH FLOODRothsayWilkin, MNROTHSAY HIGH SCHOOL FLOODED FROM EXCESSIVE RAINFALL CAUSING OVERLAND FLOODING.
23:00 UTCTSTM WND GST 80CarlisleOtter Tail, MNSEMI TRAILER OVERTURNED ALONG INTERSTATE 94
23:10 UTCHAIL 23 Ne ElizabethOtter Tail, MNSIGNIFICANT DAMAGE TO HOUSE AND CAR
23:14 UTCHAIL 0.7511 Se ErhardOtter Tail, MN
23:20 UTCHAIL 2EdwardsOtter Tail, MNPATH OF LARGE HAIL CONTINUED TO EDWARDS WHERE CONSIDERABLE ROOF AND VEHICLE DAMAGE WAS REPORTED. ALSO 3 TO 4 INCHES OF RAIN FELL.
23:34 UTCHAIL 0.7511 Se ErhardOtter Tail, MN
00:45 UTCHAIL 1.25Elbow LakeGrant, MNHAIL FELL ON NORTH END OF TOWN.
01:08 UTCHAIL 0.88AshbyGrant, MN

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2005 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of August 25, 2005

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 256:15 PM CDTF1Otter Tail, MN1.050

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.