Tornadoes · United States · South Dakota · 2013

EF1 tornado, Allen, South Dakota, May 28, 2013

This EF1 tornado ran 0.1 miles across Bennett County on May 28, 2013, touching down at 6:13 PM MDT and reaching 20 yards wide. It killed nobody and injured 1, and did $100,000 of property damage.

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 mph

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

  2. EF186 to 110 mphthis tornado

    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
EF1
Date
May 28, 2013
Touchdown
6:13 PM MDT (00:13 UTC)
Lifted
6:14 PM MDT (00:14 UTC)
On the ground
1 minutes
Path length
0.1 miles (0.2 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
1
Property damage
$100,000
County
Bennett County
Touchdown point
43.270, -101.914
Lift-off point
43.270, -101.912
Record number
1305281813-01

What the Weather Service recorded

A line of thunderstorms produced a small tornado that touched down briefly and strong straight line winds south of Allen.

A tornado touched down on the west side of Allen Road south of Allen and rolled a mobile home down a hill. It tore off the roof and collapsed several walls of a small stick built house on the east side of the road before dissipating.

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

What forecasters said that day

The local office's own words before the tornado touched down, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Rapid City, SD wrote its last area forecast discussion before the tornado touched down at May 28, 5:41 PM MDT, 32 minutes earlier.

Area forecast discussion, May 28, 5:41 PM MDT, 32 minutes before
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Hazardous weather outlook, May 28, 3:19 AM MDT, 14 hours 54 minutes before
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In the hours before

Special weather statement, May 28, 4:08 PM MDT, 2 hours 5 minutes before
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Special weather statement, May 28, 4:20 PM MDT, 1 hour 53 minutes before
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Special weather statement, May 28, 5:09 PM MDT, 1 hour 4 minutes before
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Special weather statement, May 28, 5:42 PM MDT, 31 minutes before
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Special weather statement, May 28, 5:55 PM MDT, 18 minutes before
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Special weather statement, May 28, 6:08 PM MDT, 5 minutes before
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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.

Rapid City, SD (KUNR), 00:00Z

0.2 hours before the tornado, 118 km from the path. May 29, 2013.

Skew-T log-pSkew-T log-p diagram, Rapid City, SD at 00:00Z on 2013-05-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 183 joules per kilogram, CIN -51, lifted condensation level 1923 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, Rapid City, SD at 00:00Z on 2013-05-29The 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 23 square meters per square second, 0 to 6 km bulk shear 48 knots.1939587897Sfc1 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
183 J/kg
Mixed-layer CIN
-51 J/kg
Surface CAPE
1358 J/kg
Mixed-layer LCL
1923 m above ground
0-6 km bulk shear
48 kt
0-1 km bulk shear
2 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3
0-3 km lapse rate
8.5 K/km

Open this sounding in Storm Lab

The surface observations

Pine Ridge (IEN), 56 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

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

The radar

The Rapid City radar (KUDX), 120 km away, was scanning. The volume nearest the touchdown began at 00:14 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.

This ground now

The live radar over the trackEvery 2013 tornado in South DakotaEvery tornado in South Dakota since 1950Warnings in force in South Dakota nowThe forecast where you are

The other tornadoes of May 28, 2013

24 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 283:08 PM CDTEF0Beaver, OK0.825
May 283:29 PM CDTEF0Beaver, OK1.825
May 284:16 PM CDTEF3Nemaha, KS4.4900
May 284:20 PM CDTEF1Nemaha, KS0.050
May 283:23 PM MDTEF0Sioux, NE6.375
May 284:45 PM CDTEF1Nemaha, KS0.050
May 284:05 PM MDTEF0Box Butte, NE2.250
May 285:33 PM CDTEF0Ottawa, KS0.025
May 285:45 PM CDTEF3Ottawa, KS2.31,000
May 287:35 PM EDTEF1Erie, PA1.7505$75,000
May 286:37 PM CDTEF0Barton, KS4.250
May 286:40 PM CDTEF0Rush, KS0.675
May 286:45 PM CDTEF0Deaf Smith, TX2.175
May 287:53 PM EDTEF1Erie, PA17.81502$300,000
May 288:47 PM EDTEF0Shiawassee, MI0.760$30,000
May 288:52 PM EDTEF0Shiawassee, MI0.5100$50,000
May 289:01 PM EDTEF1Genesee, MI2.3400$100,000
May 289:09 PM EDTEF1Shiawassee, MI9.9550$110,000
May 288:18 PM CDTEF0Grundy, IL1.920$5,000
May 289:25 PM EDTEF0Warren, PA2.850$10,000
May 289:30 PM EDTEF2Genesee, MI5.1500$225,000
May 289:54 PM EDTEF2Genesee, MI4.6300$350,000
May 289:58 PM EDTEF1Warren, PA4.2100$2,000
May 289:06 PM CDTEF0Deaf Smith, TX2.1150

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.