Tornadoes · United States · Iowa · 2008

EF0 tornado, Stacyville to St Ansgar Arpt, Iowa, June 7, 2008

From Stacyville to St Ansgar Arpt, this EF0 tornado ran 0.3 miles across Mitchell County on June 7, 2008, touching down at 4:50 PM CDT and reaching 30 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 7, 2008
Touchdown
4:50 PM CDT (21:50 UTC)
Lifted
4:54 PM CDT (21:54 UTC)
On the ground
4 minutes
Path length
0.3 miles (0.4 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Mitchell County
Touchdown point
43.450, -92.808
Lift-off point
43.451, -92.803
Record number
0806071550-02

What the Weather Service recorded

A warm front extending east to west across the Upper Mississippi River Valley was the focus for a severe weather event on June 7. Two brief tornadoes occurred, as reported by law enforcement officials, storm spotters, and storm chasers.||Thunderstorms also produced a brief downburst near Oelwein on June 8th.

A brief tornado touched down about 2 to 3 miles northwest of Stacyville, as reported by law enforcement officials and storm spotters. The Stacyville police chief photographed the tornado. There was no damage reported.

A storm chaser spotted a tornado near the Worth-Mitchell County line that tracked east-northeast for a short distance. There was weak debris tossed up in the air, otherwise no known 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 ARX issued a tornado warning for this county at 21:35 UTC, 15 minutes before the tornado touched down, in force until 22:15 UTC.

The county was under a tornado watch, issued at 17:20 UTC and running to 00:44 UTC.

Issued (UTC)ExpiredProductOffice
17:20 UTC00:44 UTCTornado WatchARX
21:35 UTC22:15 UTCTornado WarningARX
22:22 UTC23:00 UTCTornado WarningARX
23:00 UTC05:00 UTCFlash Flood WatchARX
23:00 UTC23:30 UTCSevere Thunderstorm WarningARX
23:03 UTC05:00 UTCFlash Flood WarningARX
00:02 UTC00:45 UTCSevere Thunderstorm WarningARX
04:46 UTC12:45 UTCFlood WarningARX

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 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 20:01 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.

Minneapolis, MN (KMPX), 12:00Z

9.8 hours before the tornado, 168 km from the path. June 7, 2008.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2008-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 131 joules per kilogram, CIN -253, lifted condensation level 1341 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, Minneapolis, MN at 12:00Z on 2008-06-07The 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 318 square meters per square second, 0 to 6 km bulk shear 74 knots.1939587897117Sfc1 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
131 J/kg
Mixed-layer CIN
-253 J/kg
Surface CAPE
9 J/kg
Mixed-layer LCL
1341 m above ground
0-6 km bulk shear
74 kt
0-1 km bulk shear
51 kt
0-1 km storm-relative helicity
318 m²/s²
0-3 km storm-relative helicity
357 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3
0-3 km lapse rate
4.4 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

2.2 hours after it, 168 km from the path. June 8, 2008.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2008-06-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -78150, lifted condensation level 1710 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 2008-06-08The 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 -22 square meters per square second, 0 to 6 km bulk shear 72 knots.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
-78150 J/kg
Surface CAPE
1 J/kg
Mixed-layer LCL
1710 m above ground
0-6 km bulk shear
72 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
288 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1
0-3 km lapse rate
6.0 K/km

Open this sounding in Storm Lab

The radar

The La Crosse radar (KARX), 136 km away, was scanning. The volume nearest the touchdown began at 21:48 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
19:15 UTCHAIL 0.54 Sw Alta VistaChickasaw, IA
19:15 UTCHAIL 0.54 Sw Alta VistaChickasaw, IA
20:02 UTCFUNNEL CLOUD1 W North WashingtonChickasaw, IA
20:02 UTCFUNNEL CLOUD1 W North WashingtonChickasaw, IA
20:25 UTCHAIL 0.54 Sw Alta VistaChickasaw, IA
20:25 UTCHAIL 0.54 Sw Alta VistaChickasaw, IA
21:15 UTCTORNADO2 Sw NorthwoodWorth, IADEBRIS CIRCULATION AT THE GROUND.
21:15 UTCTORNADO5 W NorthwoodWorth, IATORNADO SPOTTED NEAR MM214.
21:35 UTCTORNADO3 Ese NorthwoodWorth, IASMALL DEBRIS CLOUD
21:38 UTCTORNADO2 Nw StacyvilleMitchell, IASPOTTERS REPORT 2 TORNADOES ON GROUND NORTHWEST OF STACYVILLE
21:39 UTCTORNADO9 Se NorthwoodWorth, IA1 MILE WEST OF CARPENTER.
21:45 UTCTORNADO2 Nw StacyvilleMitchell, IACONFIRMED EF0 TORNADO WITH NO DAMAGE FOUND. PHOTOGRAPHED BY STACEYVILLE PD CHIEF. TORNADO TIME WINDOW 445 PM TO 450 PM.
21:45 UTCTORNADO2 Nw StacyvilleMitchell, IASPOTTERS REPORT 2 TORNADOES ON GROUND NORTHWEST OF STACYVILLE
22:45 UTCTORNADO6 N Mason City AirportCerro Gordo, IA
22:53 UTCFUNNEL CLOUD3 Ssw ManlyCerro Gordo, 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 June 7, 2008

30 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 71:52 PM CDTEF0Grant, WI0.130$750
June 71:57 PM CDTEF1Marquette, WI5.1100$302,000
June 72:32 PM CDTEF2Columbia, WI8.63,5206$2.5 million
June 73:05 PM CDTEF0Dodge, WI2.225
June 73:08 PM CDTEF1Columbia, WI2.975$200,000
June 73:16 PM CDTEF0Sauk, WI0.425
June 73:25 PM CDTEF0Dane, WI0.525
June 73:38 PM CDTEF0Dane, WI0.225
June 73:41 PM CDTEF1Winnebago, IA6.4150$250,000
June 73:49 PM CDTEF0Jefferson, WI0.150
June 74:16 PM CDTEF0Worth, IA1.775
June 74:21 PM CDTEF0Livingston, IL0.920
June 74:23 PM CDTEF0Worth, IA2.150$5,000
June 74:31 PM CDTEF1Livingston, IL3.640$50,000
June 74:40 PM CDTEF1Dane, WI3.8150$429,000
June 74:50 PM CDTEF0Houston, MN0.125
June 75:18 PM CDTEF2Kankakee, IL14.5200$500,000
June 75:28 PM CDTEF0Mitchell, IA1.125
June 75:37 PM CDTEF0Waukesha, WI0.120
June 75:42 PM CDTEF0Cerro Gordo, IA1.040$5,000
June 75:45 PM CDTEF1La Crosse, WI6.0200$93,000
June 75:48 PM CDTEF0Vernon, WI0.450$15,000
June 75:51 PM CDTEF2Will, IL2.2400$50,000
June 75:55 PM CDTEF2Will, IL3.7150$500,000
June 76:13 PM CDTEF2Will, IL6.51506$9.5 million
June 76:32 PM CDTEF1Cook, IL2.075$1.0 million
June 76:48 PM CDTEF0Cook, IL0.450$10,000
June 76:55 PM CDTEF0Osborne, KS0.150
June 78:28 PM CDTEF0Osborne, KS0.150
June 78:37 PM CDTEF0Smith, KS0.150

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.