Tornadoes · United States · Iowa · 2010

EF0 tornado, Sanborn, Iowa, June 1, 2010

This EF0 tornado ran 0.3 miles across O'Brien County on June 1, 2010, touching down at 1:22 PM CDT and reaching 50 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mphthis tornado

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. EF186 to 110 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. EF2111 to 135 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. EF3136 to 165 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. EF4166 to 200 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. EF5over 200 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
EF0
Date
June 1, 2010
Touchdown
1:22 PM CDT (18:22 UTC)
Lifted
1:23 PM CDT (18:23 UTC)
On the ground
1 minutes
Path length
0.3 miles (0.5 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
O'Brien County
Touchdown point
43.200, -95.733
Lift-off point
43.200, -95.727
Record number
1006011222-01

What the Weather Service recorded

Thunderstorms produced large hail and a brief tornado in northwest Iowa during the early afternoon of June 1st.

A brief tornado caused no reported damage.

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

The warnings

15 minutes of warning. NWS FSD issued a tornado warning for this county at 18:07 UTC, 15 minutes before the tornado touched down, in force until 18:30 UTC.

Issued (UTC)ExpiredProductOffice
18:07 UTC18:30 UTCTornado WarningFSD
18:28 UTC19:00 UTCTornado WarningFSD
18:53 UTC23:48 UTCTornado WatchFSD

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 Moderate Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 16:20 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.

Omaha, NE (KOAX), 12:00Z

6.4 hours before the tornado, 216 km from the path. June 1, 2010.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2010-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1529 joules per kilogram, CIN -110, lifted condensation level 815 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, Omaha, NE at 12:00Z on 2010-06-01The 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 80 square meters per square second, 0 to 6 km bulk shear 39 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
1529 J/kg
Mixed-layer CIN
-110 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
815 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
14 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

Omaha, NE (KOAX), 00:00Z

5.6 hours after it, 216 km from the path. June 2, 2010.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 2010-06-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 173 joules per kilogram, CIN -308, lifted condensation level 1061 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, Omaha, NE at 00:00Z on 2010-06-02The 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 -108 square meters per square second, 0 to 6 km bulk shear 49 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
173 J/kg
Mixed-layer CIN
-308 J/kg
Surface CAPE
134 J/kg
Mixed-layer LCL
1061 m above ground
0-6 km bulk shear
49 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
-108 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

The surface observations

Sheldon (SHL), 9 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
16:23 UTC8163220° 9 kt1009.8
16:28 UTC8163210° 11 kt141009.8
16:33 UTC8062230° 10 kt141009.8
16:35 UTC78.862.6220° 8 kt1009.8
16:38 UTC8063220° 9 kt1009.8
16:43 UTC8063220° 7 kt1009.8
16:48 UTC8063220° 8 kt1009.8
16:53 UTC8064220° 7 kt1009.8
16:55 UTC78.862.6220° 5 kt1009.8
16:58 UTC8064230° 5 kt1009.8
17:03 UTC8064220° 6 kt1010.2
17:08 UTC8064230° 6 kt1010.2
17:13 UTC8064230° 6 kt1010.2
17:15 UTC78.862.6230° 6 kt1010.2
17:18 UTC8064240° 6 kt1010.2
17:23 UTC8064250° 6 kt1010.2
17:28 UTC8064280° 5 kt1010.2
17:33 UTC8064310° 8 kt1010.2
17:35 UTC78.862.6340° 16 kt241010.5
17:38 UTC7861340° 22 kt271010.8
17:43 UTC7259350° 25 kt311011.2
17:48 UTC7059340° 24 kt311010.8
17:53 UTC6959340° 23 kt321010.8
17:55 UTC6859340° 23 kt321010.8
17:58 UTC6859340° 26 kt321010.8
18:03 UTC6758350° 23 kt331010.5
18:08 UTC6658350° 20 kt331010.5
18:13 UTC6658340° 23 kt301010.5
18:15 UTC64.457.2340° 29 kt331010.8-DZ
18:18 UTC6659340° 28 kt331010.2
18:23 UTC6460300° 28 kt411011.9
18:28 UTC6360330° 24 kt411011.9
18:33 UTC6260330° 18 kt311011.5
18:35 UTC60.859320° 14 kt311011.9+RA
18:38 UTC6261330° 14 kt201011.9
18:43 UTC6261340° 19 kt241011.2
18:48 UTC6261350° 16 kt241011.2
18:53 UTC6361360° 14 kt241010.8
18:55 UTC62.660.8360° 12 kt1010.8-RA
18:58 UTC636110° 13 kt1010.8
19:08 UTC636130° 10 kt1010.5
19:13 UTC636140° 11 kt1009.8
19:15 UTC62.660.840° 13 kt1009.8RA
19:18 UTC636150° 10 kt1009.5
19:23 UTC636150° 12 kt1009.5
19:28 UTC636130° 11 kt1009.1
19:33 UTC636140° 13 kt1008.5
19:35 UTC62.660.840° 13 kt1008.5
19:38 UTC646140° 11 kt1008.5
19:43 UTC646130° 8 kt1008.5
19:48 UTC656120° 9 kt1008.5
19:55 UTC64.460.810° 7 kt1008.5
19:58 UTC666120° 7 kt1008.5
20:03 UTC6762360° 7 kt1008.5
20:08 UTC676210° 7 kt1008.5
20:13 UTC686220° 6 kt1008.5
20:15 UTC6860.830° 5 kt1008.5
20:18 UTC686270° 5 kt1008.1

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

The radar

The Sioux Falls radar (KFSD), 92 km away, was scanning. The volume nearest the touchdown began at 18:21 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
18:22 UTCHAIL 1SheldonO'Brien, IAVERY HEAVY RAIN.
18:22 UTCTORNADO4 Wnw SanbornO'Brien, IABRIEF TOUCHDOWN
18:26 UTCFUNNEL CLOUD3 Wnw SanbornO'Brien, IA
18:45 UTCHAIL 1.75HartleyO'Brien, IA
18:48 UTCHAIL 1.75MonetaClay, IA
18:50 UTCHAIL 1.753 Wnw EverlyClay, IA
18:51 UTCHAIL 2.52 Ene HartleyO'Brien, IADAMAGE TO TREES AND CARS
19:10 UTCHAIL 1SpencerClay, IA
19:51 UTCHAIL 1.758 Sse RemsenPlymouth, IA

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

This ground now

The live radar over the trackEvery 2010 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

The other tornadoes of June 1, 2010

4 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 12:58 PM CDTEF0Wayne, NE1.4100
June 15:08 PM CDTEF2Ringgold, IA1.5250$4.0 million
June 16:05 PM CDTEF1Cass, NE0.6200$4,000
June 15:54 PM MDTEF0Johnson, WY0.125

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.