Tornadoes · United States · Minnesota · 2006

F1 tornado, Echols to St James, Minnesota, August 1, 2006

From Echols to St James, this F1 tornado ran 1.0 miles across Watonwan County on August 1, 2006, touching down at 7:44 PM CDT and reaching 50 yards wide. It killed nobody, and did $500,000 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
August 1, 2006
Touchdown
7:44 PM CDT (00:44 UTC)
Path length
1.0 miles (1.6 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$500,000
County
Watonwan County
Touchdown point
43.930, -94.630
Lift-off point
43.930, -94.600
Record number
783

What the Weather Service recorded

The tornado developed near Mary's Lake and moved across corn and bean fields before striking a farmstead just northwest of County Roads 10 and 27. Nearly empty grain bins were dented, sheds demolished, and a 32 foot camper was destroyed. A house lost its garage, part of its roof, and was pushed off its foundation. A large vehicle was also pushed a couple of hundred feet. Shortly after hitting the farmstead, it veered southeast into some fields, where it dissipated.

Shortly after another tornado dissipated at 1842 CST four miles south of St. James, another tornado quickly developed about 1/4 mile away. It moved across corn and bean fields until it struck a farm just southwest of County Roads 110 and 122, where it destroyed machine sheds and removed the roof of the barn. It continued moving northeast before veering to the north, where it dissipated as it hit an abandoned farmhouse.

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

The warnings

41 minutes of warning. NWS MPX issued a tornado warning for this county at 00:03 UTC, 41 minutes before the tornado touched down, in force until 00:45 UTC.

Issued (UTC)ExpiredProductOffice
00:00 UTC09:15 UTCFlash Flood WatchMPX
00:03 UTC00:45 UTCTornado WarningMPX
00:39 UTC01:30 UTCTornado WarningMPX
01:03 UTC04:41 UTCTornado WatchMPX

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 19:28 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.

Minneapolis, MN (KMPX), 00:00Z

0.7 hours before the tornado, 130 km from the path. August 2, 2006.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2006-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 778 joules per kilogram, CIN 0, lifted condensation level 476 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 2006-08-02The 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 215 square meters per square second, 0 to 6 km bulk shear 38 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
778 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
1230 J/kg
Mixed-layer LCL
476 m above ground
0-6 km bulk shear
38 kt
0-1 km bulk shear
27 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
479 m²/s²
Significant tornado parameter
1.1
Supercell composite
7.9
0-3 km lapse rate
5.4 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 12:00Z

11.3 hours after it, 130 km from the path. August 2, 2006.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2006-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2 joules per kilogram, CIN -686, lifted condensation level 582 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, Minneapolis, MN at 12:00Z on 2006-08-02The 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 22 square meters per square second, 0 to 6 km bulk shear 26 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
2 J/kg
Mixed-layer CIN
-686 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
582 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
63 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
3.3 K/km

Open this sounding in Storm Lab

The surface observations

St. James (JYG), 8 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:55 UTC84.282.470° 4 kt1008.5
23:00 UTC84.282.470° 4 kt1008.5
23:15 UTC82.482.440° 3 kt1008.1
23:20 UTC82.482.440° 3 kt1008.1
23:35 UTC82.482.450° 7 kt1007.5
23:40 UTC82.482.450° 7 kt1007.5
23:55 UTC82.480.650° 7 kt1007.5
00:00 UTC82.480.650° 7 kt1007.5
00:15 UTC80.680.640° 6 kt1007.5
00:20 UTC80.680.640° 6 kt1007.5
00:35 UTC80.680.6350° 11 kt1007.5
00:40 UTC80.680.6350° 11 kt1007.5
01:16 UTC7777280° 3 kt1007.5+TSRA
01:20 UTC7777280° 3 kt1007.5
01:35 UTC75.275.2350° 4 kt1006.4-TSRA
01:36 UTC75.275.2350° 4 kt1006.4-TSRA
01:40 UTC75.275.2350° 4 kt1006.4
01:55 UTC777720° 7 kt1006.8
02:00 UTC777720° 7 kt1006.8
02:15 UTC75.275.2360° 10 kt1006.8
02:20 UTC75.275.2360° 10 kt1006.8
02:35 UTC73.473.420° 9 kt1007.1
02:40 UTC73.473.420° 9 kt1007.1

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

The radar

The Minneapolis radar (KMPX), 132 km away, was scanning. The volume nearest the touchdown began at 00:42 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
23:54 UTCTORNADO3 Se Mountain LakeCottonwood, MNBRIEF TOUCHDOWN OF F0 TORNADO
00:19 UTCTORNADO2 Sw ButterfieldWatonwan, MNIN PROGRESS AT 719 PM SOUTHWEST OF BUTTERFIELD. TORNADO ROPED OUT AT 722 PM. TORNADO HAD DEBRIS FIELD AS IT DISSIPATED. CHASER NOTED ANOTHER TORNADO APPEARED IMMINENT TO DEVELOP.
00:19 UTCTORNADO3 S ButterfieldWatonwan, MNIN PROGRESS...BETWEEN BUTTERFIELD AND ODIN.
00:43 UTCTORNADO3 S ButterfieldWatonwan, MNSTRUCTURAL DAMAGE REPORTED AT FARM HOUSE. CALLED IN AT 743 PM. UNKNOWN IF IT WAS THE SAME TORNADO AS PREVIOUSLY REPORTED. NO INJURIES.
00:44 UTCTORNADO1 N South BranchWatonwan, MNNEW TORNADO ON GROUND WITH DEBRIS NEAR COUNTY ROADS 27 AND 10. APPEARS TO BE MOVING EAST-SOUTHEAST.
00:47 UTCFUNNEL CLOUD1 N OdinWatonwan, MNFUNNEL APPEARS LIKE IT WILL SOON REACH THE GROUND.
00:48 UTCTORNADO4 S St JamesWatonwan, MNSTRUCTURAL DAMAGE REPORTED AT FARM HOUSE. UNCERTAIN IF THIS WAS THE SAME TORNADO AS PREVIOUSLY REPORTED. DAMAGE CALLED IN AT 748 PM. NO INJURIES.
01:00 UTCTSTM WND GST 85JacksonJackson, MN8 INCH DIAMETER TREES DOWN
01:00 UTCTSTM WND GST 85JacksonJackson, MN
01:05 UTCTSTM WND DMGDunnellMartin, MNTREES DOWN. CORN FLATTENED.
01:35 UTCTSTM WND DMGFairmontMartin, MNTREE DOWN. KSUM ON WEST SIDE OF TOWN MEASURED 54 MPH. PONDING OF WATER IN SOME INTERSECTIONS.
03:05 UTCFLASH FLOODBlue EarthFaribault, MNSTREET FLOODING. WATER FLOWING INTO SOME BASEMENTS.

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

This ground now

The live radar over the trackEvery 2006 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of August 1, 2006

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 16:54 PM CDTF0Cottonwood, MN0.150
August 17:14 PM CDTF3Watonwan, MN1.5440$2.0 million
August 17:33 PM CDTF1Watonwan, MN3.0100$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.