Tornadoes · United States · Iowa · 2007

EF3 tornado, Grandview to Muscatine, Iowa, June 1, 2007

From Grandview to Muscatine, this EF3 tornado ran 15.8 miles across Louisa and Muscatine counties on June 1, 2007, touching down at 12:07 PM CDT and reaching 774 yards wide. It killed nobody and injured 7, and did $16 million 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 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 mphthis tornado

    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
EF3
Date
June 1, 2007
Touchdown
12:07 PM CDT (17:07 UTC)
Lifted
12:31 PM CDT (17:31 UTC)
On the ground
24 minutes
Path length
15.8 miles (25.3 km)
Path width
774 yards (708 m)
Deaths
0
Injuries
7
Property damage
$16 million
Counties
Louisa and Muscatine counties
Touchdown point
41.269, -91.194
Lift-off point
41.459, -91.028
Record number
0706011107-01

What the Weather Service recorded

A line of thunderstorms pivoted northeast into parts of southeast Iowa during the mid-morning hours of June 1st. Much of the area was just breaking out of a blanket of dense fog where visibilities dropped to less than a quarter mile. Dew point temperatures were in the middle 60s to around 70 degrees. ||The line of storms appeared to become more broken through the late morning hours, while the area from Iowa City to Waterloo appeared to stratify out into a large area of showers. Just before 12:00 pm CDT, rapid intensification of storm cells on the southeast end of the original line occurred as it moved into northern portions of Louisa County. ||A tornado touched down just south of Grandview, IA and moved northeast through Fruitland, IA and on to the southwest parts of Muscatine, IA. The tornado then lifted and as the storm cell continued to move northeast across Muscatine County. The super-cell re-intensified as it entered the southeast part of Cedar County just before 1 pm producing a brief tornado near Wilton, IA. The storm then moved across northwest parts of Scott County and Clinton County producing damaging wind gusts and large hail. The super-cell continued northeast into Jackson County producing a tornado near Bellevue around 2:30 pm, which moved across the Mississippi River into Jo Daviess County before lifting. The storm produced yet another tornado just south of Scales Mound, IL around 3:15 pm before moving into southwest Wisconsin and dissipating.||During the early afternoon hours, additional storms strengthened on the south end of the original line of storms, which went on to produce wind damage and large hail as they moved through northwest Illinois through the late afternoon hours.

The tornado touched down on the southern edge of Grandview. It moved through the center of town intensifying in rural areas as it approached the county line. In Grandview, several homes sustained severe damage. North of Grandview, about 1.5 miles, a farm house was completely destroyed. Other homes and trees along the path sustained damage. The tornado crossed the Louisa-Muscatine county line just south of Fruitland, IA.|

A tornado entered into Muscatine County from Louisa County just south of Fruitland, IA. It progressed to the northeast through the center of Fruitland destroying the post office and city hall building, numerous homes, and overturning some railroad cars. The tornado weakened as it approached the southwest portions of Muscatine. In Muscatine, the western sections of town had varying degrees of damage, which was mainly confined to roof damage. At a car dealership, some cars were displaced. The tornado eventually lifted on the northeast side of Muscatine near the junction of highways 22 and 61. Debris from Muscatine and Fruitland fell in Lowden, IA. Some personal papers were found 1 to 4 miles northwest of Lowden. Lowden is approximately 30 miles NNE of Muscatine.|

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.

Issued (UTC)ExpiredProductOffice
11:03 UTC14:00 UTCDense Fog AdvisoryDVN
17:09 UTC17:40 UTCTornado WarningDVN
17:37 UTC21:08 UTCTornado WatchDVN

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 17:32 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

5.1 hours before the tornado, 58 km from the path. June 1, 2007.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2007-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 259 joules per kilogram, CIN -43, lifted condensation level 871 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 2007-06-01The 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 47 square meters per square second, 0 to 6 km bulk shear 33 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
259 J/kg
Mixed-layer CIN
-43 J/kg
Surface CAPE
393 J/kg
Mixed-layer LCL
871 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
47 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 00:00Z

6.9 hours after it, 58 km from the path. June 2, 2007.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2007-06-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 21 joules per kilogram, CIN -79, lifted condensation level 1264 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 00:00Z on 2007-06-02The 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 59 square meters per square second, 0 to 6 km bulk shear 12 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
21 J/kg
Mixed-layer CIN
-79 J/kg
Surface CAPE
185 J/kg
Mixed-layer LCL
1264 m above ground
0-6 km bulk shear
12 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
59 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.7 K/km

Open this sounding in Storm Lab

The surface observations

Muscatine (MUT), 2 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
15:49 UTC7370130° 7 kt1011.9
15:59 UTC7370120° 6 kt1011.9
16:09 UTC7370130° 9 kt1011.9
16:19 UTC7370100° 9 kt1011.2
16:29 UTC7370100° 8 kt141010.8
16:35 UTC71.669.8110° 9 kt1010.8-RA
16:39 UTC7370100° 7 kt1010.8
16:49 UTC737090° 8 kt1009.8
16:55 UTC71.669.8100° 9 kt1009.5-RA
16:59 UTC7371100° 8 kt1009.5
17:06 UTC7371110° 7 kt1009.5

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

The radar

The Quad Cities radar (KDVN), 52 km away, was scanning. The volume nearest the touchdown began at 17:05 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
17:09 UTCTORNADO2 N WapelloLouisa, IATORNADO ON GROUND REPORTED BY PUBLIC NEAR HIGHWAY 92 NORTH OF WAPELLO.
17:15 UTCTORNADOGrandviewLouisa, IASEVERE DAMAGE TO HOMES. CITY OF GRANDVIEW CORDONED OFF BY POLICE DUE TO THE DAMAGE. DELAYED REPORT.
17:19 UTCTORNADO3 W MuscatineMuscatine, IATRAINED SPOTTER REPORTS TORNADO AT BURLINGTON ROAD NEAR THE AIRPORT.
17:25 UTCTORNADOMuscatineMuscatine, IASEMI TRAILER TRUCKS OVERTURNED AT THE INDUSTRIAL CENTER IN MUSCATINE. DELAYED REPORT.
17:26 UTCTORNADOMuscatineMuscatine, IATORNADO ON THE GROUND NEAR THE BYPASS IN MUSCATINE. DEBRIS IN THE AIR. POSSIBLE DAMAGE.
17:32 UTCTORNADO1 N MuscatineMuscatine, IATORNADO ON THE GROUND NORTH SIDE OF MUSCATINE. DEBRIS FLYING INTO THE AIR.
17:44 UTCTORNADO6 Sw BennettCedar, IANWS STORM SURVEY SHOWED EF1 TORNADO TRACK APPROXIMATELY 6 MILES SOUTHWEST OF BENNETT. 1 MILE LONG AND 75 YARDS WIDE. TREES WERE SNAPPED.
17:51 UTCTORNADO1 Nw WiltonCedar, IATORNADO ON THE GROUND WITH DEBRIS IN THE AIR NW OF WILTON.
18:40 UTCTSTM WND GST 60DavenportScott, IAESTIMATED 60 MPH WINDS AT THE WALMART NEAR ELMORE AND I-74.
19:30 UTCTSTM WND DMG1 Ne Pleasant ValleyScott, IATREES BLOWN DOWN

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

This ground now

The live radar over the trackEvery 2007 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

The other tornadoes of June 1, 2007

9 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 112:55 PM EDTEF0Monroe, FL0.630$20,000
June 112:44 PM CDTEF1Cedar, IA1.175
June 12:28 PM CDTEF2Jackson, IA to IL3.4350$3.3 million
June 13:15 PM CDTEF0Jo Daviess, IL0.510
June 13:17 PM CDTEF0Lafayette, WI0.120
June 13:31 PM CDTEF0Lafayette, WI0.230
June 16:30 PM CDTEF0Hamilton, IA0.130
June 17:25 PM CDTEF0Gaines, TX2.550
June 19:45 PM EDTEF1Miami-Dade, FL3.975$20,000

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.