EF3 tornado, Villisca to Carl, Iowa, May 21, 2024

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.

Rating

EF3

Date

May 21, 2024

Touchdown

2:43 PM CDT (19:43 UTC)

Lifted

3:21 PM CDT (20:21 UTC)

On the ground

38 minutes

Path length

33.9 miles (54.5 km)

Path width

1,300 yards (1189 m)

Deaths

0

Injuries

0

Property damage

$1.0 million

Counties

Page, Montgomery and Adams counties

Touchdown point

40.856, -95.201

Lift-off point

41.155, -94.688

Record number

2405211343-01

233 damage points were recorded along this path by NWS DMX and NWS OAX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF4. The highest wind the damage implies is 180 mph.

• Damage to hooped greenhouse, covers partially removed
• Trunks of large trees snapped, with some shingles removed from old house a short distance away
• Complete destruction of newly built machine shed.
• Lots of limbs broken, a few trunks snapped

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

Troughing over the western CONUS brought southwesterly flow aloft over the central and northern Plains for the duration of this event. In the couple of days leading up to May 21st, the upper-level flow pattern amplified as a trough deepened over the northern Rockies. This trough then ejected out into the central Plains on the 21st. At the surface, a stationary front developed and stretched across central Nebraska and southern Iowa by the evening of the 19th. Elevated convection that morning north of the developing surface boundary resulted in isolated instances of severe hail and wind across southeast Nebraska. Additional scattered strong to severe thunderstorms developed along this frontal boundary as it slowly lifted north, with a 64 miles per hour wind gust measured in Lancaster County and golf ball sized hail falling in Clarinda Iowa.|A weak low-pressure system developed the morning of the 20th in response to a shortwave rounding the base of the main trough out west, resulting in a cold front that pushed southeast across South Dakota and central Nebraska that afternoon. This front, however, stalled out across eastern Nebraska and western Iowa that evening, remaining draped across the region that night and into the morning of the 21st. Numerous rounds of strong and severe thunderstorms that night brought widespread severe weather and flash flooding, primarily across east-central Nebraska and southwest Iowa, though some elevated supercells in northeast Nebraska brought small hail to the area. After 10 UTC, an intense line of severe thunderstorms moved across eastern Nebraska and western Iowa bringing wind gusts ranging from 60 to 95 miles per hour, in addition to several spin-up tornadoes. |As the primary upper level disturbance ejected out over the Great Plains, intense surface cyclogenesis was noted over eastern Nebraska. This resulted in the frontal boundary that had been draped across eastern Nebraska and western Iowa that night prior to be forced northward. By 18 UTC, a strong cold front pushed through southeast Nebraska and into Iowa that afternoon. Scattered supercell thunderstorms developed along this cold front and moved across southeast Nebraska and western Iowa. These supercells became tornadic after crossing the Missouri River into Iowa, with several long-track significant tornadoes being confirmed across the state. In the OAX CWA, the strongest tornado damage confirmed was that consistent of an EF-2 in Montgomery County. This tornado continued into the DMX CWA where it caused EF-3 damage. Another tornado developed in Page County shortly before 3 PM that afternoon. This tornado went on to produce EF-4 damage in the DMX CWA. All in all, over this three-day event, 10 tornadoes were confirmed across the OAX CWA.

PLEASE NOTE, for hail, wind, heavy rain and flooding, please see separate Storm Data entry for May 20-22. ||Numerous tornadoes occurred on this day with numerous injuries and four fatalities at Greenfield in Adair County.||Multiple rounds of thunderstorms brought torrential rainfall, damaging winds, hail and destructive tornadoes to the state. These thunderstorms were the result of a low pressure system which lifted north into the area on the night of May 20th, 2024, producing slow moving storms that dropped 2 to 4 inches of rainfall. This resulted in flash flooding over portions of northern and central Iowa through the morning of May 21st, 2024.||Following the heavy rainfall through the morning, skies cleared out ahead of an approaching cold front. By the afternoon hours of May 21st, 2024, this cold front produced a line of strong thunderstorms which produced multiple strong tornadoes throughout the state, including one which led to significant damage in the town of Greenfield, IA, among other locations. This line of storms also produced damaging winds, leading to widespread tree damage and power outages throughout the forecast area.

This is a continuation of the Adams County EF-3 tornado as it came out of Page County. This tornado crossed into southern Montgomery County just east of the Montgomery-Page Street and O Avenue intersection. As the tornado continued to the northeast, it tracked through several homesteads snapping tree trunks and destroying multiple farm outbuildings. As the tornado crossed 250th Street, a radio tower was destroyed resulting in EF-2 damage. Further to the northwest at a homestead at the intersection of 240th Street and T Avenue, a home took a direct hit with the majority of its roof blown off in addition to the loss of several exterior walls on the second floor. Trees on the property were uprooted and farm outbuilding were completely destroyed and swept away. This is the strongest damage from this tornado in Montgomery County, rated EF-2 with estimated wind speeds of 130 mph. The tornado then crossed US Highway 71 three-quarters of a mile south of US Highway 34, causing damage to trees and destroying an attached garage to a residence. The walls of the garage were bolted to the foundation and had been completely swept away. The remaining house had significant roof damage, but all the walls remained. Afterwards, the tornado crossed US Highway 34 on the south side of the Hacklebarney Woods County Park. Here trees were snapped, small outbuildings were destroyed and a camping trailer was rolled on its side. The tornado then continued northeast, causing damage to outbuildings and snapping tree trunks as it crossed Vine Avenue. The tornado then crossed into Adams County (see Des Moines National Weather Service StormData) approximately two-thirds of a mile north of 210th Street.

The tornado entered into Adams County after clipping the northwest corner of Taylor County. Damage was immediate on the county border with damage to trees and and to farm buildings and power poles within the first few miles in the county. The tornado continued to gain in strength and size as it travelled northeast through southwest Adams county remaining in rural areas south and east of Nodaway. The tornado eventually crossed Federal Highway 34 just north of Brooks with plenty of videos showing a large funnel with debris swirling below it. As the tornado crossed State Highway 148, it gained in strength with EF2 damage becoming more common. Upon reaching the intersection of 150th Street and Notchwood Avenue, EF3 damage occurred with much of an unanchored house losing walls and sliding off the foundation. All outbuildings at this site were also destroyed. As the tornado continued into the north central portion of the county, it encountered several industrial wind mills. Several of the towers collapsed along with the large blades being tossed hundreds of feet through the air. The tornado was multi-vortex at this point with a width of 1300 yards. The tornado exited the county into Adair County between Quince Avenue and Redwood Avenue. The was one death in the county from this tornado when a female driver was ejected from a vehicle which got caught within the circulation.

The tornado entered into Adams County from Montgomery County. This tornado remained in rural areas of western and northern Adams County until lifting north of the town of Carl near the Adair County line. The tornado impacted a house on the north side of 200th street shortly after entering the county removing much of the roof with general collapse of the structure. A large hog confinement facility near the intersection of 190th and Aspen was severally damage with most buildings destroyed. EF3 damage occurred to a house along 175th Street near Cherry Avenue with all wall removed except a couple of the interior walls. The outbuildings at this location were all destroyed as well. Another house along 150th Street near Dogwood Avenue had all but a few interior walls removed with EF3 damage as well. All outbuildings were destroyed at this site as well. The tornado turned slightly to the right at this point with only limited interaction with building sites but plenty of tree damage for the remainder of it path.

The deaths

1 direct deaths are recorded for this tornado, each with what Storm Data knows of it.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

NWS Omaha, NE wrote its last area forecast discussion before the tornado touched down at May 21, 12:25 PM CDT, 2 hours 18 minutes earlier. Its key messages:

• Continuing overnight convection will bring potential for severe weather this morning, primarily damaging winds and flash flooding.
• Additional strong to severe thunderstorms with all hazards possible will move through the area in the 10 AM to 2 PM timeframe today.
• There will be additional rain chances beginning Thursday night and lasting through this upcoming weekend.

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1225 PM CDT Tue May 21 2024

.KEY MESSAGES...

- Continuing overnight convection will bring potential for
  severe weather this morning, primarily damaging winds and
  flash flooding.

- Additional strong to severe thunderstorms with all hazards
  possible will move through the area in the 10 AM to 2 PM
  timeframe today.

- There will be additional rain chances beginning Thursday night
  and lasting through this upcoming weekend.

&&

.DISCUSSION...
Issued at 205 AM CDT Tue May 21 2024

Short Range (Today)

A deep upper level trough moving into the central Plains has spun up
a surface low currently sitting in western Kansas. Overnight
convection in the area forced by a leading shortwave continues to
weaken through the overnight hours. This has brought a shift from a
severe weather threat to a hydrologic threat with storm training
along a frontal boundary draped across east central Nebraska
bringing flash flooding potential to the area. Nearly 2 inches of
rainfall has been reported for the Omaha area overnight.

An MCS has developed over southwest Nebraska/northeast CO and will
quickly accelerate eastward overnight. The features is expected to
push through the area in the 5:30 to 7:30 am period. CAM guidance is
suggesting a strong segment of bowing winds pushing through the area
in this timeframe. The strongest winds will likely be north of
Interstate 80 with the HRRR suggesting gusts of 60-70 mph in
portions of northeast Nebraska.

A lull in convection is expected in the 8 am to 11 am timeframe with
a few lingering showers possible. By the mid-morning, the
aforementioned surface low is expected to deepen and track
northeast into eastern Nebraska. Guidance has continued to slow
the progression of this low with consensus gained on the feature
reaching northeast NE by noon. This has prompted to SPC to
expand the moderate risk (level 4 out of 5) for severe weather
westward to include our southwestern Iowa counties. An
associated cold front will drape south of the low with
placement over eastern Nebraska by late morning. The airmass
ahead of the cold front is expected to quickly recover from the
overnight convection. By late morning, MLCAPE values of
2500-2800 J/kg are expected in southeast NE and southwest IA.
Bulk shear values are expected to exceed 70 kts in this area as
a 500-mb jet streak pushes into the region. Hodographs remain
long with increasingly impressive low level features as your
progress eastward into Iowa.

Convection initiation is expected along the front in eastern
Nebraska during the 10 AM to noon timeframe. An initial
supercellular storm mode is expected before storms move northeast
and take on upscale growth. All hazards will be possible including
large hail, strong winds and tornadoes. Flash flood potential is
possible through much of Tuesday, especially for areas that received
increased rainfall overnight. Storms will be quick to exit the area
this afternoon with much of the threat shifting east by 3 to 4 PM.
Additional lingering rain showers may continue into the
early evening.

Long Range (Wednesday through Monday)

By Wednesday, the aforementioned low pressure system is expected to
depart towards the Great Lakes region. Dry conditions are expected
with sunny skies and highs in the upper 70s. A shortwave trough
ejecting through the northern Plains will bring a chance for
rainfall Thursday night into Friday morning (PoPs 50-70%). Severe
weather potential is low with this event. An additional shortwave
feature moving across the Plains this weekend will bring additional
rainfall potential Saturday night through Sunday. PoPs remain low at
this time (20-40%). In this extended time frame, severe weather
potential looks to remain south of the area with this event.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1222 PM CDT Tue May 21 2024

IFR to MVFR conditions at TAF issuance with thunderstorms
expected through about 20z, then showers through about 00z, and
eventually transitioning back to VFR 21z to 01z. Southeasterly
winds at KLNK/KOMA becoming northwest, 20 to 35 knots.

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Flood Watch until 7 PM CDT this evening for NEZ015-033-034-
     042>045-050>053-065>068-078.
IA...Flood Watch until 7 PM CDT this evening for IAZ043-055-056-069-
     079-080-090-091.

&&

DISCUSSION...Wood
AVIATION...DeWald

Hazardous Weather Outlook
National Weather Service Omaha/Valley NE
1138 AM CDT Tue May 21 2024

IAZ043-055-056-069-079-080-090-091-NEZ011-012-015>018-030>034-
042>045-050>053-065>068-078-088>093-220645-
Monona-Harrison-Shelby-Pottawattamie-Mills-Montgomery-Fremont-
Page-Knox-Cedar-Thurston-Antelope-Pierce-Wayne-Boone-Madison-
Stanton-Cuming-Burt-Platte-Colfax-Dodge-Washington-Butler-
Saunders-Douglas-Sarpy-Seward-Lancaster-Cass-Otoe-Saline-
Jefferson-Gage-Johnson-Nemaha-Pawnee-Richardson-
1138 AM CDT Tue May 21 2024

This Hazardous Weather Outlook is for portions of southwest
Iowa...west central Iowa...east central Nebraska...northeast
Nebraska and southeast Nebraska.

.DAY ONE...This Afternoon and Tonight

Severe storms will again be possible through mid afternoon, from
now through about 3 pm. Large hail, damaging wind gusts, and
tornadoes will be possible. Flash flooding could also occur for
those areas that received 3 to 7 inches of rain earlier today. A
tornado watch is in effect most areas east of Highway 81.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

There's a marginal risk of severe weather on Thursday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will be required for many areas today.

In the hours before

Preliminary Local Storm Report
National Weather Service Omaha/Valley NE
218 PM CDT Tue May 21 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0216 PM     Funnel Cloud     3 SSE Imogene           40.84N 95.42W
05/21/2024                   Fremont            IA   Broadcast Media

            Funnel cloud reported by broadcast media
            extending halfway to the ground. This was
            just south of Imogene.

&&

BD

Preliminary Local Storm Report
National Weather Service Omaha/Valley NE
225 PM CDT Tue May 21 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 AM     Tstm Wnd Dmg     1 SSW Inglewood         41.40N 96.51W
05/21/2024                   Saunders           NE   NWS Employee

            Numerous large trees down across Valley View
            Estates and Valley View Golf Course. Delayed
            report.

&&

Preliminary Local Storm Report
National Weather Service Omaha/Valley NE
227 PM CDT Tue May 21 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0225 PM     Funnel Cloud     3 ENE Imogene           40.89N 95.37W
05/21/2024                   Page               IA   Trained Spotter

            Trained spotter reported a funnel cloud and
            rotation in the far northwest corner of Page
            County.

&&

BD

Preliminary Local Storm Report
National Weather Service Omaha/Valley NE
235 PM CDT Tue May 21 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0233 PM     Funnel Cloud     5 ESE Emerson           40.98N 95.32W
05/21/2024                   Montgomery         IA   Emergency Mngr

            Emergency Manager reported another funnel
            developing to the southwest of Red Oak.

&&

BD

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Red Oak (RDK), 27 km from the path, in the two hours either side.

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

The Omaha radar (KOAX), 124 km away, was scanning. The volume nearest the touchdown began at 19:45 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.

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

42 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.