Tornadoes · United States · South Dakota · 2012
EF0 tornado, Willow Lake, South Dakota, June 1, 2012
This EF0 tornado ran 0.6 miles across Clark County on June 1, 2012, touching down at 9:14 PM CDT and reaching 10 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.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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, 2012
- Touchdown
- 9:14 PM CDT (02:14 UTC)
- Lifted
- 9:16 PM CDT (02:16 UTC)
- On the ground
- 2 minutes
- Path length
- 0.6 miles (1.0 km)
- Path width
- 10 yards (9 m)
- Deaths
- 0
- Injuries
- 0
- County
- Clark County
- Touchdown point
- 44.580, -97.640
- Lift-off point
- 44.573, -97.632
- Record number
- 1206012014-01
What the Weather Service recorded
An upper level short wave trough brought a few severe thunderstorms which produced quarter size hail along with a few tornado touchdowns.
A tornado touched down briefly north of Willow Lake with no damage reported.
A tornado touched down briefly south of Willow Lake with no damage occuring.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
24 minutes of warning. NWS ABR issued a tornado warning for this county at 01:50 UTC, 24 minutes before the tornado touched down, in force until 02:15 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 00:31 UTC | 01:00 UTC | Tornado Warning | ABR |
| 00:57 UTC | 01:45 UTC | Severe Thunderstorm Warning | ABR |
| 01:04 UTC | 01:30 UTC | Tornado Warning | ABR |
| 01:50 UTC | 02:15 UTC | Tornado Warning | ABR |
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 01:01 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), 00:00Z
2.2 hours before the tornado, 70 km from the path. June 2, 2012.
- Mixed-layer CAPE
- 443 J/kg
- Mixed-layer CIN
- -19 J/kg
- Surface CAPE
- 1098 J/kg
- Mixed-layer LCL
- 1068 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 149 m²/s²
- 0-3 km storm-relative helicity
- 215 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 2.9
- 0-3 km lapse rate
- 7.6 K/km
Aberdeen, SD (KABR), 12:00Z
9.8 hours after it, 70 km from the path. June 2, 2012.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -86331 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 1267 m above ground
- 0-6 km bulk shear
- 62 kt
- 0-1 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 62 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
- 3.7 K/km
The radar
The Aberdeen radar (KABR), 115 km away, was scanning. The volume nearest the touchdown began at 02:13 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 00:59 UTC | TORNADO | 3 E Raymond | Clark, SD | |
| 01:02 UTC | HAIL 1 | Clark | Clark, SD | |
| 01:48 UTC | TORNADO | 5 N Willow Lake | Clark, SD | |
| 02:14 UTC | TORNADO | 3 S Willow Lake | Clark, SD |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2012 tornado in South DakotaEvery tornado in South Dakota since 1950Warnings in force in South Dakota nowThe forecast where you are
The other tornadoes of June 1, 2012
25 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| June 1 | 2:29 PM EDT | EF0 | Montgomery, MD | 0.6 | 150 | $5,000 | ||
| June 1 | 2:37 PM EDT | EF0 | Montgomery, MD | 0.6 | 50 | $5,000 | ||
| June 1 | 2:48 PM EDT | EF0 | Carroll, MD | 0.4 | 100 | $5,000 | ||
| June 1 | 2:52 PM EDT | EF1 | Howard, MD | 2.1 | 200 | $5,000 | ||
| June 1 | 3:09 PM EDT | EF0 | Montgomery, MD | 0.5 | 75 | $50,000 | ||
| June 1 | 3:21 PM EDT | EF1 | Carroll, MD | 2.9 | 150 | $200,000 | ||
| June 1 | 4:29 PM EDT | EF0 | Howard, MD | 1.6 | 150 | $100,000 | ||
| June 1 | 4:32 PM EDT | EF0 | York, PA | 0.0 | 25 | $25,000 | ||
| June 1 | 5:13 PM EDT | EF0 | Okeechobee, FL | 0.9 | 20 | |||
| June 1 | 5:18 PM EDT | EF0 | Pasquotank, NC | 0.6 | 50 | |||
| June 1 | 5:25 PM EDT | EF1 | Westmoreland, PA | 4.8 | 300 | $3.0 million | ||
| June 1 | 5:27 PM EDT | EF0 | Prince George's, MD | 0.9 | 50 | $2,000 | ||
| June 1 | 5:46 PM EDT | EF0 | Anne Arundel, MD | 0.1 | 75 | $3,000 | ||
| June 1 | 5:56 PM EDT | EF1 | Harford, MD | 1.2 | 300 | 2 | $300,000 | |
| June 1 | 6:18 PM EDT | EF0 | Bedford, PA | 1.5 | 75 | $25,000 | ||
| June 1 | 5:27 PM CDT | EF0 | Brown, SD | 0.5 | 10 | |||
| June 1 | 6:31 PM EDT | EF1 | Allegany, MD | 1.1 | 175 | $2,000 | ||
| June 1 | 7:02 PM EDT | EF0 | City of Petersburg, VA | 3.0 | 150 | 5 | $175,000 | |
| June 1 | 7:06 PM EDT | EF0 | Anne Arundel, MD | 6.6 | 100 | $100,000 | ||
| June 1 | 7:17 PM EDT | EF0 | Hanover, VA | 1.8 | 100 | |||
| June 1 | 8:13 PM EDT | EF1 | City of Hampton, VA | 3.2 | 500 | $1.0 million | ||
| June 1 | 8:30 PM EDT | EF0 | Queen Anne's, MD | 5.0 | 50 | $100,000 | ||
| June 1 | 7:59 PM CDT | EF0 | Clark, SD | 2.4 | 20 | |||
| June 1 | 9:08 PM EDT | EF0 | Northampton, VA | 0.7 | 75 | $3,000 | ||
| June 1 | 8:48 PM CDT | EF0 | Clark, SD | 0.5 | 10 |
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.