Tornadoes · United States · Iowa · 2024

EF0 tornado, Charles City to Carrville, Iowa, May 9, 2024

From Charles City to Carrville, this EF0 tornado ran 0.6 miles across Floyd County on May 9, 2024, touching down at 1:03 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
May 9, 2024
Touchdown
1:03 PM CDT (18:03 UTC)
Lifted
1:05 PM CDT (18:05 UTC)
On the ground
2 minutes
Path length
0.6 miles (1.0 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Floyd County
Touchdown point
43.022, -92.672
Lift-off point
43.020, -92.659
Record number
2405091203-01

What the Weather Service recorded

During the afternoon of May 9th, multiple sources reported a landspout tornado associated with a weak thunderstorm south of Charles City, IA. No damage was reported with this landspout tornado.

Multiple sources reported a very short lived non-supercell tornado south of Charles City, IA. Video footage showed a brief touchdown in an open field. No damage was observed.

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
18:11 UTC18:27 UTCTornado WarningARX
21:00 UTC15:29 UTCFlood WarningDMX

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 General Thunderstorms Risk. The outlook in force was issued at 16:46 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

6.1 hours before the tornado, 217 km from the path. May 9, 2024.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2024-05-09Temperature 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 -97551, lifted condensation level 729 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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 2024-05-09The 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 7 square meters per square second, 0 to 6 km bulk shear 17 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
0 J/kg
Mixed-layer CIN
-97551 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
729 m above ground
0-6 km bulk shear
17 kt
0-1 km bulk shear
2 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
34 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.4 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

5.9 hours after it, 217 km from the path. May 10, 2024.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2024-05-10Temperature 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 -93050, lifted condensation level 2067 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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 2024-05-10The 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 11 square meters per square second, 0 to 6 km bulk shear 17 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
0 J/kg
Mixed-layer CIN
-93050 J/kg
Surface CAPE
44 J/kg
Mixed-layer LCL
2067 m above ground
0-6 km bulk shear
17 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
54 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
8.6 K/km

Open this sounding in Storm Lab

The radar

The La Crosse radar (KARX), 149 km away, was scanning. The volume nearest the touchdown began at 18:03 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
18:15 UTCFUNNEL CLOUD4 S Charles CityFloyd, IANumerous reports of funnel clouds from near Charles City to south of Charles City from 1257pm until 125pm. Possible tornado from video at 115pm.
18:15 UTCLANDSPOUT4 S Charles CityFloyd, IANumerous reports of funnel clouds south of Charles City from 1257pm until 125pm. Brief landspout around 115pm per video and law enforcement observations. No damage reported.

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

This ground now

The live radar over the trackEvery 2024 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

The other tornadoes of May 9, 2024

18 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 91:39 AM CDTEF0Benton, TN1.3100$3,000
May 92:46 AM EDTEF0Newberry, SC3.0150
May 93:12 AM EDTEF0Fairfield, SC0.350
May 93:31 AM EDTEF1Fairfield, SC1.9250
May 93:44 AM CDTEF1Lincoln, TN4.2105
May 94:01 AM CDTEF1Lincoln, TN to AL13.7215
May 94:06 AM CDTEF1Lincoln, TN to AL6.1300
May 94:10 AM CDTEF1Lincoln, TN10.2194
May 94:31 AM CDTEF1Jackson, AL0.3108$155,000
May 94:37 AM CDTEF1Jackson, AL1.1170$165,000
May 95:08 AM CDTEF1Jackson, AL6.1241$138,000
May 912:50 PM EDTEF1Dodge, GA12.2150
May 91:06 PM EDTEF0Laurens, GA8.6100
May 91:18 PM EDTEF0Wheeler, GA7.2150
May 91:39 PM EDTEF1Montgomery, GA14.7250
May 98:19 PM EDTEF1Wood, WV3.42501$15,000
May 98:55 PM EDTEF0Preston, WV0.450$50,000
May 910:11 PM CDTEF0Hinds, MS4.9105$40,000

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.