Tornadoes · United States · Iowa · 2024
EF0 tornado, Madrid to Napier, Iowa, May 24, 2024
From Madrid to Napier, this EF0 tornado ran 10.7 miles across Boone County on May 24, 2024, touching down at 4:42 AM CDT and reaching 180 yards wide. It killed nobody, and did $10,000 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.
EF065 to 85 mphthis tornado
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.
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 24, 2024
- Touchdown
- 4:42 AM CDT (09:42 UTC)
- Lifted
- 4:54 AM CDT (09:54 UTC)
- On the ground
- 12 minutes
- Path length
- 10.7 miles (17.2 km)
- Path width
- 180 yards (165 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $10,000
- County
- Boone County
- Touchdown point
- 41.895, -93.931
- Lift-off point
- 41.941, -93.733
- Record number
- 2405240342-01
What the Weather Service recorded
A strong QLCS moved across central Iowa during the early morning hours of May 24 producing widespread wind damage and five tornadoes.
This QLCS tornado started a few miles north of Woodward and moved eastward quickly. Most of the damage along the entire path was to trees although one farmstead south of Luther had damage to one of the outbuildings. The tornado lifted to the south of Napier in eastern Boone County.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
28 minutes of warning. NWS DMX issued a tornado warning for this county at 09:14 UTC, 28 minutes before the tornado touched down, in force until 09:45 UTC.
The county was under a severe thunderstorm watch, issued at 07:44 UTC and running to 11:07 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 07:44 UTC | 11:07 UTC | Severe Thunderstorm Watch | DMX |
| 08:56 UTC | 09:45 UTC | Severe Thunderstorm Warning | DMX |
| 09:00 UTC | 18:00 UTC | Flood Watch | DMX |
| 09:14 UTC | 09:45 UTC | Tornado Warning | DMX |
| 09:28 UTC | 10:00 UTC | Tornado Warning | DMX |
| 09:40 UTC | 10:30 UTC | Severe Thunderstorm Warning | DMX |
| 09:41 UTC | 10:15 UTC | Tornado Warning | DMX |
| 09:46 UTC | 10:07 UTC | Tornado Warning | DMX |
| 12:00 UTC | 15:01 UTC | Flood Watch | DMX |
| 17:39 UTC | 19:03 UTC | Flood Warning | DMX |
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 05:52 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.
Omaha, NE (KOAX), 00:00Z
9.7 hours before the tornado, 221 km from the path. May 24, 2024.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -100176 J/kg
- Surface CAPE
- 184 J/kg
- Mixed-layer LCL
- 2328 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 61 m²/s²
- 0-3 km storm-relative helicity
- 226 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 7.4 K/km
Omaha, NE (KOAX), 12:00Z
2.3 hours after it, 221 km from the path. May 24, 2024.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -91020 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 1012 m above ground
- 0-6 km bulk shear
- 67 kt
- 0-1 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- -89 m²/s²
- 0-3 km storm-relative helicity
- -2 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
- 0-3 km lapse rate
- 4.0 K/km
The radar
The Des Moines radar (KDMX), 23 km away, was scanning. The volume nearest the touchdown began at 09:42 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 |
|---|---|---|---|---|
| 08:05 UTC | HAIL 0.88 | Elkhart | Polk, IA | Pea to nickel sized hail in Elkhart. Delayed report. |
| 08:20 UTC | HAIL 1.25 | 4 Ssw Nevada | Story, IA | Social Media report between Cambridge and Nevada. |
| 08:20 UTC | HAIL 1.25 | 4 Ssw Nevada | Story, IA | Social Media report between Cambridge and Nevada. |
| 08:30 UTC | HAIL 1 | Nevada | Story, IA | |
| 08:30 UTC | HAIL 1 | Nevada | Story, IA | |
| 09:32 UTC | TSTM WND GST 63 | 3 Wsw Perry | Dallas, IA | Peak wind at Perry Airport. |
| 09:32 UTC | TSTM WND GST 63 | 3 Wsw Perry | Dallas, IA | Peak wind at Perry Airport. |
| 09:40 UTC | TSTM WND DMG | Boxholm | Boone, IA | Delayed social media picture of power poles down near Boxholm. Time estimated by radar. |
| 09:40 UTC | TSTM WND DMG | Boxholm | Boone, IA | Delayed social media picture of power poles down near Boxholm. Time estimated by radar. |
| 09:40 UTC | TSTM WND GST 65 | 2 N Patterson | Madison, IA | Reported by Trained Spotter. |
| 09:40 UTC | TSTM WND GST 65 | 2 N Patterson | Madison, IA | Reported by Trained Spotter. |
| 09:47 UTC | TSTM WND DMG | Madrid | Boone, IA | Corrects previous tstm wnd dmg report from Madrid. Large branch and power line down in street. |
| 09:47 UTC | TSTM WND DMG | Madrid | Boone, IA | Corrects previous tstm wnd dmg report from Madrid. Large branch and power line down in street. |
| 09:47 UTC | TSTM WND DMG | Madrid | Boone, IA | Large branch and power line down in street. |
| 09:55 UTC | TSTM WND DMG | 1 Nnw West Des Moines | Polk, IA | Delayed report of a tree down on a house. Time estimated from radar. |
| 09:55 UTC | TSTM WND DMG | Johnston | Polk, IA | Delayed report. Social media picture of large tree branches down in Johnston. Time estimated by radar. |
| 09:55 UTC | TSTM WND DMG | Johnston | Polk, IA | Delayed report. Social media picture of large tree branches down in Johnston. Time estimated by radar. |
| 09:55 UTC | TORNADO | 1 E Johnston | Polk, IA | NWS damage survey identified damage consistent with an EF0 tornado that tracked from southern into eastern portions of Johnston from 453 AM to 457 AM. |
| 10:00 UTC | TSTM WND DMG | 2 Sse Ames | Story, IA | Delayed social media report of a large tree down on the south side of Ames. Time estimated by radar. |
| 10:00 UTC | TSTM WND DMG | 2 Sse Ames | Story, IA | Delayed social media report of a large tree down on the south side of Ames. Time estimated by radar. |
| 10:04 UTC | TSTM WND DMG | 1 Sw Perry | Dallas, IA | Several larger trees down in Perry. 3500 without power in Perry. |
| 10:04 UTC | TSTM WND DMG | 1 Sw Perry | Dallas, IA | Several larger trees down in Perry. 3500 without power in Perry. |
| 10:04 UTC | TSTM WND GST 58 | Johnston | Polk, IA | Personal weather station. |
| 10:04 UTC | TSTM WND GST 58 | Johnston | Polk, IA | Personal weather station. |
| 10:07 UTC | TSTM WND DMG | 1 Se Ames | Story, IA | Large tree snapped on S Duff on the south edge of town. Time and location estimated with radar. Relayed with social media. |
| 10:07 UTC | TSTM WND DMG | 1 Se Ames | Story, IA | Large tree snapped on S Duff on the south edge of town. Time and location estimated with radar. Relayed with social media. |
| 10:08 UTC | TSTM WND DMG | 3 E Pleasant Hill | Polk, IA | Report from mPING: 1-inch tree limbs broken; Shingles blown off. |
| 10:08 UTC | TSTM WND DMG | 3 E Pleasant Hill | Polk, IA | Report from mPING: 1-inch tree limbs broken; Shingles blown off. |
| 10:13 UTC | TSTM WND GST 60 | 1 W Webster City | Hamilton, IA | |
| 10:13 UTC | TSTM WND GST 60 | 1 W Webster City | Hamilton, IA | |
| 10:15 UTC | TSTM WND DMG | 6 N Ellsworth | Hamilton, IA | Delayed report of semis tipped over on I35 near mile marker 139, along with power line damage. Time estimated from radar. |
| 10:15 UTC | TSTM WND DMG | 6 N Ellsworth | Hamilton, IA | Delayed report of semis tipped over on I35 near mile marker 139, along with power line damage. Time estimated from radar. |
| 10:20 UTC | TSTM WND GST 75 | Mingo | Jasper, IA | Winds estimated 70 to 80 from Sheriff deputy. |
| 10:20 UTC | TSTM WND GST 75 | Mingo | Jasper, IA | Winds estimated 70 to 80 from Sheriff deputy. |
| 10:22 UTC | TSTM WND GST 68 | 3 E Colfax | Jasper, IA | Personal weather station. |
| 10:22 UTC | TSTM WND GST 68 | 3 E Colfax | Jasper, IA | Personal weather station. |
| 10:22 UTC | HAIL 1.5 | Prairie City | Jasper, IA | Ping pong hail briefly fell followed by winds. Time estimated with radar. |
| 10:22 UTC | HAIL 1.5 | Prairie City | Jasper, IA | Ping pong hail briefly fell followed by winds. Time estimated with radar. |
| 10:26 UTC | TSTM WND DMG | Prairie City | Jasper, IA | Powerlines and trees down. Campers flipped. Time estimated with radar. |
| 10:26 UTC | TSTM WND DMG | Prairie City | Jasper, IA | Powerlines and trees down. Campers flipped. Time estimated with radar. |
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 24, 2024
42 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 24 | 1:08 AM CDT | EF1 | Platte, NE | 11.8 | 700 | |||
| May 24 | 1:13 AM CDT | EF1 | Platte, NE | 1.3 | 50 | |||
| May 24 | 1:30 AM CDT | EF1 | Colfax, NE | 4.8 | 400 | |||
| May 24 | 1:43 AM CDT | EF0 | Seward, NE | 0.0 | 20 | |||
| May 24 | 1:50 AM CDT | EF0 | Dodge, NE | 1.1 | 75 | |||
| May 24 | 2:03 AM CDT | EF0 | Saunders, NE | 0.1 | 20 | |||
| May 24 | 2:12 AM CDT | EF0 | Saunders, NE | 0.1 | 60 | |||
| May 24 | 2:18 AM CDT | EF0 | Washington, NE | 3.4 | 60 | |||
| May 24 | 2:18 AM CDT | EF0 | Washington, NE | 1.8 | 60 | |||
| May 24 | 2:25 AM CDT | EF0 | Sarpy, NE | 0.1 | 50 | |||
| May 24 | 2:32 AM CDT | EF0 | Sarpy, NE | 0.5 | 60 | |||
| May 24 | 2:35 AM CDT | EF0 | Sarpy, NE | 3.7 | 300 | |||
| May 24 | 2:41 AM CDT | EF1 | Harrison, IA | 0.7 | 150 | |||
| May 24 | 3:00 AM CDT | EF0 | Pottawattamie, IA | 0.3 | 60 | |||
| May 24 | 3:08 AM CDT | EF1 | Sevier, AR | 8.2 | 300 | $500,000 | ||
| May 24 | 3:10 AM CDT | EF0 | Montgomery, IA | 2.1 | 60 | |||
| May 24 | 3:13 AM CDT | EF0 | Shelby, IA | 0.1 | 40 | |||
| May 24 | 3:22 AM CDT | EF0 | Montgomery, IA | 1.2 | 30 | |||
| May 24 | 4:38 AM CDT | EF0 | Dallas, IA | 9.2 | 80 | $60,000 | ||
| May 24 | 4:53 AM CDT | EF0 | Polk, IA | 3.2 | 100 | $50,000 | ||
| May 24 | 4:57 AM CDT | EF0 | Warren, IA | 2.2 | 50 | $2,000 | ||
| May 24 | 5:07 AM CDT | EF0 | Polk, IA | 1.5 | 50 | $90,000 | ||
| May 24 | 5:10 AM CDT | EF1 | Hamilton, IA | 2.9 | 75 | $80,000 | ||
| May 24 | 5:56 AM CDT | EF1 | Keokuk, IA | 7.2 | 70 | |||
| May 24 | 6:26 AM CDT | EF1 | Washington, IA | 18.3 | 100 | |||
| May 24 | 6:45 AM CDT | EF1 | Washington, IA | 22.5 | 150 | |||
| May 24 | 6:55 AM CDT | EF1 | Muscatine, IA | 15.0 | 75 | |||
| May 24 | 7:12 AM CDT | EF0 | Johnson, IA | 0.1 | 50 | |||
| May 24 | 7:20 AM CDT | Unrated | Cedar, IA | 11.0 | 10 | |||
| May 24 | 7:30 AM CDT | EF1 | Cedar, IA | 15.0 | 50 | |||
| May 24 | 7:36 AM CDT | Unrated | Scott, IA | 0.1 | 10 | |||
| May 24 | 7:45 AM CDT | EF1 | Scott, IA | 15.3 | 50 | |||
| May 24 | 7:52 AM CDT | EF1 | Rock Island, IL | 20.2 | 50 | |||
| May 24 | 7:52 AM CDT | EF1 | Scott, IA | 7.2 | 50 | |||
| May 24 | 8:09 AM CDT | Unrated | Scott, IA | 0.8 | 10 | |||
| May 24 | 8:21 AM CDT | Unrated | Clinton, IA | 0.3 | 10 | |||
| May 24 | 8:50 AM CDT | Unrated | Henry, IL | 0.3 | 10 | |||
| May 24 | 9:12 AM CDT | Unrated | Whiteside, IL | 1.0 | 10 | |||
| May 24 | 9:31 AM CDT | Unrated | Bureau, IL | 0.5 | 10 | |||
| May 24 | 2:52 PM CDT | Unrated | Richland, ND | 0.5 | 10 | |||
| May 24 | 5:24 PM EDT | EF1 | Onslow, NC | 8.8 | 150 | |||
| May 24 | 7:05 PM CDT | EF1 | Bowie, TX | 1.8 | 275 |
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.