Tornadoes · United States · Iowa · 2008

EF0 tornado, Charlotte to Goose Lake, Iowa, August 4, 2008

From Charlotte to Goose Lake, this EF0 tornado ran 8.0 miles across Clinton County on August 4, 2008, touching down at 5:47 PM CDT and reaching 250 yards wide. It killed nobody, and did $250,000 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 4, 2008
Touchdown
5:47 PM CDT (22:47 UTC)
Lifted
6:05 PM CDT (23:05 UTC)
On the ground
18 minutes
Path length
8.0 miles (12.8 km)
Path width
250 yards (229 m)
Deaths
0
Injuries
0
Property damage
$250,000
County
Clinton County
Touchdown point
42.013, -90.456
Lift-off point
41.916, -90.370
Record number
0808041647-01

What the Weather Service recorded

A cold front slowly moved southeast into eastern Iowa during the daytime hours of August 4. South to southwest winds brought increased heat and humidity with high temperatures that ranged from 82 at Freeport, IL to 99 at Muscatine, IA. Heat index readings were as high as 120 degrees.||Late that afternoon and evening, an upper level disturbance moved along the cold front triggering showers and thunderstorms over northeast Iowa and northwest Illinois. Some of the storms produced brief heavy rains, large hail, and damaging winds, with one storm in particular developing a tornado between Charlotte, IA and Goose Lake, IA.

An EF0 tornado damaged three farmsteads along a path from 3.2 miles north northeast of Charlotte, IA to 4 miles south southwest of Goose Lake, IA between 547 pm and 605 pm August 4. Several outbuildings were damaged with the total loss of the roofing on many of them. Many trees and branches were damaged, with several large trees blown down or snapped off.

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 21:48 UTC and running to 00:47 UTC.

Issued (UTC)ExpiredProductOffice
21:48 UTC00:47 UTCSevere Thunderstorm WatchDVN
22:14 UTC23:15 UTCSevere Thunderstorm WarningDVN
22:37 UTC23:15 UTCSevere Thunderstorm WarningDVN
22:54 UTC23:30 UTCTornado WarningDVN

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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 22:44 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.

Davenport, (KDVN), 12:00Z

10.8 hours before the tornado, 39 km from the path. August 4, 2008.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2008-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2467 joules per kilogram, CIN -204, lifted condensation level 1334 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, Davenport, at 12:00Z on 2008-08-04The 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 149 square meters per square second, 0 to 6 km bulk shear 24 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
2467 J/kg
Mixed-layer CIN
-204 J/kg
Surface CAPE
2612 J/kg
Mixed-layer LCL
1334 m above ground
0-6 km bulk shear
24 kt
0-1 km bulk shear
30 kt
0-1 km storm-relative helicity
149 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 00:00Z

1.2 hours after it, 39 km from the path. August 5, 2008.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2008-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 6781 joules per kilogram, CIN -3, lifted condensation level 790 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Davenport, at 00:00Z on 2008-08-05The 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 163 square meters per square second, 0 to 6 km bulk shear 48 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
6781 J/kg
Mixed-layer CIN
-3 J/kg
Surface CAPE
6662 J/kg
Mixed-layer LCL
790 m above ground
0-6 km bulk shear
48 kt
0-1 km bulk shear
22 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
239 m²/s²
Significant tornado parameter
7.9
Supercell composite
32.9
0-3 km lapse rate
6.8 K/km

Open this sounding in Storm Lab

The radar

The Quad Cities radar (KDVN), 42 km away, was scanning. The volume nearest the touchdown began at 22:47 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
22:00 UTCHAIL 0.25CascadeDubuque, IA
22:15 UTCHAIL 0.881 Wsw CascadeJones, IA
22:25 UTCTSTM WND GST 451 N MonmouthJackson, IA
22:33 UTCTSTM WND DMGCottonvilleJackson, IASEVERAL LARGE OAK TREES DOWN. TREE DAMAGE EXTENDS EAST ACROSS COUNTY TOWARDS SOUTHERN BELLEVUE AREA.
22:36 UTCHAIL 0.25BellevueJackson, IA
22:42 UTCTSTM WND DMG1 S BellevueJackson, IAAT LEAST 20 LARGE TREES DOWN IN KURTH ADDITION ROUGHLY ONE HALF MILE SOUTH OF BELLEVUE. POWER LINES DOWN.
22:47 UTCTORNADO3 Nne CharlotteClinton, IACONVERGENT DAMAGE PATH ON FARMSTEAD AND NEARBY WOODS BEGAN 3.2 MILES NNE OF CHARLOTTE...AND DAMAGE PATH ENDED 4 MILES SSE OF GOOSE LAKE AT 605 PM CDT.
22:50 UTCHAIL 0.88CascadeDubuque, IATIME ESTIMATED
22:52 UTCTSTM WND GST 604 Ese MaquoketaJackson, IA
22:55 UTCTSTM WND GST 70MilesJackson, IA
23:00 UTCTSTM WND DMGGoose LakeClinton, IATREES DOWN. RELAYED FROM BROADCAST MEDIA. DELAYED REPORT.
23:00 UTCTSTM WND GST 76Goose LakeClinton, IARELAYED BY BROADCAST MEDIA. DELAYED REPORT.
23:05 UTCTORNADO4 Sse Goose LakeClinton, IACONVERGENT DAMAGE PATH BEGAN 3.2 MILES NNE OF CHARLOTTE AT 547 PM CDT...AND ENDED 4 MILES SSE OF GOOSE LAKE AT 605 PM CDT.
23:07 UTCTSTM WND GST 52StocktonMuscatine, IA
23:08 UTCTSTM WND GST 60ClintonClinton, IAWIND BLOWING VEHICLE ON HWY 67 NORTH SIDE OF TOWN

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 4, 2008

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 42:00 PM PDTEF1San Bernardino, CA1.1100$10,000
August 47:45 PM CDTEF1DuPage, IL0.640$40,000
August 47:45 PM CDTEF1Will, IL1.150$500,000
August 47:47 PM CDTEF1DuPage, IL0.850$250,000
August 47:59 PM CDTEF0Cook, IL0.330$30,000
August 48:27 PM CDTEF2Lake, IN2.730$1.0 million
August 412:20 AM EDTEF0Benton, IN0.110$5,000

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.