Tornadoes · United States · Iowa · 2019
Unrated tornado, Plainview to Donahue, Iowa, July 9, 2019
From Plainview to Donahue, this Unrated tornado ran 0.0 miles across Scott County on July 9, 2019, touching down at 7:41 PM CDT and reaching 10 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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
Unratedthis tornado
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
- Unrated
- Date
- July 9, 2019
- Touchdown
- 7:41 PM CDT (00:41 UTC)
- Lifted
- 7:42 PM CDT (00:42 UTC)
- On the ground
- 1 minutes
- Path length
- 0.0 miles (0.1 km)
- Path width
- 10 yards (9 m)
- Deaths
- 0
- Injuries
- 0
- County
- Scott County
- Touchdown point
- 41.668, -90.662
- Lift-off point
- 41.668, -90.662
- Record number
- 1907091841-01
The damage survey
2 damage points were recorded along this path by NWS DVN, in the Damage Assessment Toolkit the survey teams carry.
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
What the Weather Service recorded
Severe thunderstorms moved across eastern Iowa during the early evening. These low topped supercells interacted with a warm front that was draped across eastern Iowa and prodcued two brief tornado touchdowns near Walcott and Donahue. No damage was reported or observed with these touchdowns.
Iowa State Troopers observed a brief tornado near the intersection of 230th Street and 60th Avenue, just north of the I-80 Truckstop in Walcott. The tornado caused no damage from which the National Weather Service could assign an EF-scale rating.
A trained spotter observed a brief tornado in an open field. The tornado caused no damage from which the National Weather Service could assign an EF-scale rating.
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.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 16:00 UTC | 19:35 UTC | Heat Advisory | DVN |
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 Marginal Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:55 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), 00:00Z
0.7 hours before the tornado, 14 km from the path. July 10, 2019.
- Mixed-layer CAPE
- 802 J/kg
- Mixed-layer CIN
- -12 J/kg
- Surface CAPE
- 3258 J/kg
- Mixed-layer LCL
- 1120 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 187 m²/s²
- 0-3 km storm-relative helicity
- 280 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 9.8
- 0-3 km lapse rate
- 6.4 K/km
Davenport, (KDVN), 12:00Z
11.3 hours after it, 14 km from the path. July 10, 2019.
- Mixed-layer CAPE
- 1189 J/kg
- Mixed-layer CIN
- -97 J/kg
- Surface CAPE
- 1377 J/kg
- Mixed-layer LCL
- 1187 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 41 m²/s²
- 0-3 km storm-relative helicity
- 63 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
- 0-3 km lapse rate
- 4.3 K/km
The surface observations
Quad Cities (DVN), 8 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 22:45 UTC | 170° 11 kt | 1012.5 | ||||
| 22:50 UTC | 160° 11 kt | 1012.5 | ||||
| 22:52 UTC | 84 | 74 | 160° 11 kt | 1012.2 | ||
| 22:55 UTC | 160° 10 kt | 1012.2 | ||||
| 23:00 UTC | 170° 9 kt | 1012.2 | ||||
| 23:05 UTC | 170° 10 kt | 1012.2 | ||||
| 23:10 UTC | 170° 8 kt | 1012.2 | ||||
| 23:15 UTC | 180° 14 kt | 1012.2 | ||||
| 23:20 UTC | 14 kt | 1012.2 | ||||
| 23:25 UTC | 170° 11 kt | 1012.2 | ||||
| 23:30 UTC | 170° 11 kt | 18 | 1012.2 | |||
| 23:35 UTC | 170° 10 kt | 15 | 1012.2 | |||
| 23:40 UTC | 170° 9 kt | 1012.2 | ||||
| 23:45 UTC | 160° 10 kt | 15 | 1011.9 | |||
| 23:50 UTC | 160° 11 kt | 1011.9 | ||||
| 23:52 UTC | 83 | 72 | 170° 9 kt | 19 | 1011.9 | |
| 23:55 UTC | 170° 9 kt | |||||
| 00:00 UTC | 160° 9 kt | 1011.9 | ||||
| 00:05 UTC | 160° 13 kt | 1011.9 | ||||
| 00:10 UTC | 170° 10 kt | 15 | 1011.9 | |||
| 00:12 UTC | 83 | 72 | 170° 12 kt | 18 | 1011.9 | VCTS |
| 00:15 UTC | 170° 9 kt | 15 | 1011.9 | |||
| 00:20 UTC | 170° 10 kt | 1011.9 | ||||
| 00:25 UTC | 180° 7 kt | 1011.9 | ||||
| 00:30 UTC | 170° 8 kt | 1011.9 | ||||
| 00:32 UTC | 83 | 73 | 170° 7 kt | 1011.9 | ||
| 00:35 UTC | 160° 8 kt | 1011.9 | ||||
| 00:40 UTC | 150° 8 kt | 1011.9 | ||||
| 00:45 UTC | 160° 11 kt | 1011.9 | ||||
| 00:50 UTC | 170° 9 kt | 14 | 1011.9 | |||
| 00:52 UTC | 83 | 73 | 170° 10 kt | 1011.9 | ||
| 00:55 UTC | 170° 10 kt | 1011.9 | ||||
| 01:00 UTC | 180° 11 kt | 1011.9 | ||||
| 01:05 UTC | 190° 10 kt | 1011.9 | ||||
| 01:10 UTC | 200° 9 kt | 1011.9 | ||||
| 01:15 UTC | 200° 11 kt | 1011.9 | ||||
| 01:20 UTC | 190° 9 kt | 1011.9 | ||||
| 01:25 UTC | 190° 10 kt | 1011.9 | ||||
| 01:30 UTC | 190° 10 kt | 1011.9 | ||||
| 01:35 UTC | 190° 9 kt | 1012.2 | ||||
| 01:40 UTC | 190° 9 kt | 1012.2 | ||||
| 01:45 UTC | 190° 8 kt | 1012.2 | ||||
| 01:50 UTC | 190° 7 kt | 1012.2 | ||||
| 01:52 UTC | 82 | 73 | 190° 8 kt | 1012.2 | ||
| 01:55 UTC | 190° 8 kt | 1012.2 | ||||
| 02:00 UTC | 190° 7 kt | 1012.2 | ||||
| 02:05 UTC | 190° 7 kt | 1012.2 | ||||
| 02:10 UTC | 190° 7 kt | 1012.2 | ||||
| 02:15 UTC | 190° 8 kt | 1012.5 | ||||
| 02:20 UTC | 200° 7 kt | 1012.5 | ||||
| 02:25 UTC | 200° 8 kt | 1012.5 | ||||
| 02:30 UTC | 190° 7 kt | 1012.5 | ||||
| 02:35 UTC | 190° 9 kt | 1012.9 | ||||
| 02:40 UTC | 190° 8 kt | 1012.9 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Quad Cities radar (KDVN), 9 km away, was scanning. The volume nearest the touchdown began at 00:40 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 22:42 UTC | FUNNEL CLOUD | Calamus | Clinton, IA | ROTATING WALL CLOUD WITH BRIEF FUNNEL EXTENDING HALF WAY TO THE GROUND EAST OF CALAMUS. FEATURE HAS SINCE DISSIPATED. |
| 00:00 UTC | HEAVY RAIN 0.34 | Camanche | Clinton, IA | RAINFALL IN 30 MINUTES. |
| 00:05 UTC | TORNADO | 1 W Walcott | Scott, IA | STATE TROOPERS REPORTED A BRIEF TORNADO TOUCHDOWN NEAR WALCOTT AT APPROXIMATELY 7:05 PM. THE FEATURE HAD SINCE DISSIPATED, BUT ROTATION IN THE CLOUDS AS STILL SEEN TO THE NORTH OF WALCOTT. |
| 00:08 UTC | FUNNEL CLOUD | 2 S Massillon | Cedar, IA | BRIEF FUNNEL. |
| 00:41 UTC | FUNNEL CLOUD | 3 Sse Donahue | Scott, IA | BRIEF FUNNEL CLOUD SEEN TO NORTHWEST OF NWS OFFICE. LASTED LESS THAN 1 MINUTE. LOCATION APPROXIMATE. |
| 00:41 UTC | TORNADO | 2 Sse Donahue | Scott, IA | A TRAINED SPOTTER OBSERVED A BRIEF TORNADO IN AN OPEN FIELD. THE TORNADO CAUSED NO DAMAGE FROM WHICH THE NWS COULD ASSIGN AN EF-SCALE RATING. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2019 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are
The other tornadoes of July 9, 2019
8 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| July 9 | 5:19 PM CDT | EF1 | Richland, ND | 1.5 | 100 | |||
| July 9 | 5:30 PM CDT | EF0 | Richland, ND | 0.2 | 50 | |||
| July 9 | 5:57 PM CDT | EF1 | Wilkin, MN | 2.0 | 100 | |||
| July 9 | 5:58 PM CDT | EF0 | Clay, MN | 0.5 | 75 | |||
| July 9 | 6:20 PM CDT | EF1 | Wilkin, MN | 0.9 | 150 | |||
| July 9 | 6:30 PM CDT | EF0 | Clay, MN | 3.0 | 150 | |||
| July 9 | 6:45 PM CDT | EF1 | Otter Tail, MN | 2.0 | 150 | |||
| July 9 | 7:08 PM CDT | Unrated | Scott, IA | 0.1 | 10 |
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.