Tornadoes · United States · Iowa · 2008

EF0 tornado, Lake Park, Iowa, August 13, 2008

This EF0 tornado ran 0.3 miles across Dickinson County on August 13, 2008, touching down at 6:08 PM CDT and reaching 50 yards wide. It killed nobody, and did $5,000 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 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 13, 2008
Touchdown
6:08 PM CDT (23:08 UTC)
Lifted
6:10 PM CDT (23:10 UTC)
On the ground
2 minutes
Path length
0.3 miles (0.5 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$5,000
County
Dickinson County
Touchdown point
43.470, -95.300
Lift-off point
43.473, -95.295
Record number
0808131708-01

What the Weather Service recorded

A tornado and a damaging wind report accompanied numerous reports of large hail across northwest Iowa during the late afternoon and early evening of August 13th.

A tornado damaged several outbuildings and tore half the roof off a hog confinement building.

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

The warnings

3 minutes of warning. NWS FSD issued a tornado warning for this county at 23:05 UTC, 3 minutes before the tornado touched down, in force until 23:30 UTC.

The county was under a severe thunderstorm watch, issued at 21:45 UTC and running to 02:03 UTC.

Issued (UTC)ExpiredProductOffice
21:45 UTC02:03 UTCSevere Thunderstorm WatchFSD
22:46 UTC23:30 UTCSevere Thunderstorm WarningFSD
23:05 UTC23:30 UTCTornado WarningFSD
23:28 UTC00:00 UTCSevere Thunderstorm WarningFSD
23:52 UTC00:30 UTCSevere Thunderstorm 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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 20:00 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), 12:00Z

11.1 hours before the tornado, 205 km from the path. August 13, 2008.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2008-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 178 joules per kilogram, CIN -86, lifted condensation level 1447 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, Minneapolis, MN at 12:00Z on 2008-08-13The 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 78 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
178 J/kg
Mixed-layer CIN
-86 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1447 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
14 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
138 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2
0-3 km lapse rate
4.5 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

0.9 hours after it, 205 km from the path. August 14, 2008.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2008-08-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 33 joules per kilogram, CIN -56, lifted condensation level 1910 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, Minneapolis, MN at 00:00Z on 2008-08-14The 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 35 square meters per square second, 0 to 6 km bulk shear 22 knots.1939Sfc1 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
33 J/kg
Mixed-layer CIN
-56 J/kg
Surface CAPE
1040 J/kg
Mixed-layer LCL
1910 m above ground
0-6 km bulk shear
22 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2
0-3 km lapse rate
7.8 K/km

Open this sounding in Storm Lab

The surface observations

Worthington (OTG), 31 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:15 UTC78.862.6170° 8 kt1010.5
21:35 UTC78.862.6180° 12 kt1010.8
21:55 UTC78.862.6200° 9 kt1010.8
22:15 UTC7762.6220° 9 kt1010.8
22:35 UTC75.264.4290° 8 kt1011.2VCTS
22:55 UTC64.455.4340° 14 kt201012.9TS
23:15 UTC60.857.280° 15 kt201011.5TS
23:35 UTC62.657.2140° 8 kt1011.2
23:55 UTC64.455.4160° 8 kt1011.2
00:15 UTC66.257.2260° 5 kt1010.8
00:35 UTC66.2590° 0 kt1011.2
00:55 UTC66.259190° 4 kt1011.2

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

The radar

The Sioux Falls radar (KFSD), 116 km away, was scanning. The volume nearest the touchdown began at 23:08 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
23:08 UTCTSTM WND DMG2 Ne Lake ParkDickinson, IAHALF OF A HOG BARN DESTROYED
23:08 UTCTORNADO2 Ne Lake ParkDickinson, IABRIEF F0 TORNADO CAUSED DAMAGE TO A FEW OUT BUILDINGS.
23:17 UTCTSTM WND GST 60Lake ParkDickinson, IA
23:17 UTCHAIL 1.75Lake ParkDickinson, IA
23:21 UTCHAIL 2Lake ParkDickinson, IA
23:30 UTCHAIL 0.883 N GeorgeLyon, IA
23:33 UTCHAIL 12 Sw WahpetonDickinson, IA
23:48 UTCHAIL 0.756 Ene DickensClay, IA
23:54 UTCHAIL 0.756 Ene DickensClay, IA
00:10 UTCHAIL 0.881 N RuthvenPalo Alto, IAKICD STAFFER REPORTED THE HAIL IN THE RUTHVEN/LOST ISLAND LAKE AREA.
00:15 UTCHAIL 1RoyalClay, IA

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

This ground now

The live radar over the trackEvery 2008 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

The other tornadoes of August 13, 2008

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 134:16 PM MDTEF1El Paso, CO1.3100$10,000
August 135:10 PM MDTEF0Crowley, CO0.350
August 136:41 PM MDTEF0Deuel, NE0.420
August 139:00 PM EDTEF0Lake, FL0.130$12,000
August 139:00 PM EDTEF0Lake, FL0.130$12,000

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.