Tornadoes · United States · South Dakota · 2010

EF0 tornado, Plano to Epiphany, South Dakota, August 3, 2010

From Plano to Epiphany, this EF0 tornado ran 0.9 miles across Hanson and Miner counties on August 3, 2010, touching down at 6:57 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
August 3, 2010
Touchdown
6:57 PM CDT (23:57 UTC)
Lifted
6:59 PM CDT (23:59 UTC)
On the ground
2 minutes
Path length
0.9 miles (1.4 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Counties
Hanson and Miner counties
Touchdown point
43.840, -97.820
Lift-off point
43.850, -97.810
Record number
1008031757-01

What the Weather Service recorded

Thunderstorms produced a tornado, damaging winds, and flash flooding in southeast South Dakota, mostly near Interstate 90, during the evening of August 3rd.

A brief tornado near the county line raised dust, but caused no reported damage. The tornado crossed briefly into Miner County before dissipating.

A brief tornado caused no reported damage. The tornado crossed into Miner County from Hanson County before quickly dissipating.

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.

The county was under a severe thunderstorm watch, issued at 23:55 UTC and running to 02:54 UTC.

Issued (UTC)ExpiredProductOffice
23:55 UTC02:54 UTCSevere Thunderstorm WatchFSD
23:58 UTC00:30 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 General Thunderstorms Risk. The outlook in force was issued at 19:45 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

12.0 hours before the tornado, 126 km from the path. August 3, 2010.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 12:00Z on 2010-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 742 joules per kilogram, CIN -73, lifted condensation level 1307 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 2010-08-03The 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 40 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
742 J/kg
Mixed-layer CIN
-73 J/kg
Surface CAPE
55 J/kg
Mixed-layer LCL
1307 m above ground
0-6 km bulk shear
40 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8
0-3 km lapse rate
3.7 K/km

Open this sounding in Storm Lab

Aberdeen, SD (KABR), 00:00Z

0.0 hours before the tornado, 126 km from the path. August 4, 2010.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 2010-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 210 joules per kilogram, CIN -69, lifted condensation level 1753 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 2010-08-04The 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 -49 square meters per square second, 0 to 6 km bulk shear 42 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
210 J/kg
Mixed-layer CIN
-69 J/kg
Surface CAPE
1378 J/kg
Mixed-layer LCL
1753 m above ground
0-6 km bulk shear
42 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
-49 m²/s²
0-3 km storm-relative helicity
-30 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-1.2
0-3 km lapse rate
6.9 K/km

Open this sounding in Storm Lab

The radar

The Sioux Falls radar (KFSD), 92 km away, was scanning. The volume nearest the touchdown began at 23:58 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
23:57 UTCTORNADO8 N FultonHanson, SDBRIEF TOUCHDOWN WITH DUST LIFTED
23:59 UTCTORNADO8 N FultonMiner, SD
02:10 UTCTSTM WND GST 609 Ne PlankintonAurora, SDSEVERAL BRANCHES DOWN
02:15 UTCHEAVY RAIN 2.511 W LetcherAurora, SD2.50 INCHES OF RAIN IN ONE HOUR.
02:20 UTCTSTM WND GST 60Wnw Mount VernonDavison, SD

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 South DakotaEvery tornado in South Dakota since 1950Warnings in force in South Dakota nowThe forecast where you are

The other tornadoes of August 3, 2010

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 311:02 AM MDTEF0Campbell, WY0.110$1,000
August 34:22 PM EDTEF1Montgomery, NY0.250
August 34:29 PM EDTEF1Montgomery, NY0.275
August 35:15 PM MSTEF0Apache, AZ1.040
August 39:35 PM EDTEF0Caledonia, VT0.150$25,000

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.