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Tornado outbreak kills at least seven in Iowa with severe damage near Des Moines area

The outbreak delivered multiple intense tornadoes with long tracks across the Hawkeye State

Cleanup efforts are underway in Winterset, Iowa, on Sunday after a tornado tore near the town. (Bryon Houlgrave/Associated Press)
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At least seven people are dead, two of them children younger than 5, after multiple tornadoes swept across central and southwest Iowa on Saturday, officials said Sunday.

Six of the fatalities came from Madison County, just southwest of Des Moines, including the storm’s youngest victims, said Madison County Emergency Management Director Diogenes Ayala. Four people were also injured, including one who was taken to the hospital with life-threatening injuries, he said. One person living in a destroyed camper was killed in rural Lucas County, county officials confirmed Sunday.

The National Weather Service received 42 reports of tornadoes in the south central and southwest portions of the Hawkeye State (some of these are duplicate reports from the same twister), part of an early season outbreak that was worse than forecasters feared.

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The most destructive tornado was described as “large and extremely dangerous” by the Weather Service, with a number of “particularly dangerous situation” tornado warnings issued. The parent rotating thunderstorm or supercell tracked upward of 150 miles, and it was probable that the main Madison County tornado could have been on the ground for more than an hour.

Madison County is home to the city of Winterset, which was ravaged by the twister. About 25 miles southwest of Des Moines, Winterset is the county seat and best known as the birthplace of actor John Wayne.

“This is the worst anyone has seen in quite a long time,” Ayala said at a predawn news conference Sunday. “This will be impactful for many years to come.” The Weather Service tweeted that the damage near Winterset was consistent with a twister that would earn a rating of at least 3 on the scale from 0 to 5 for tornado intensity.

Violent winds ripped through an area along Carver Road, roughly three miles outside Winterset. Ayala estimated 20 to 30 homes on both sides of the road were destroyed, with the damage localized outside the city. State and local first responders from around Iowa were pouring into the hardest-hit areas to help with search efforts, Ayala said. Early Sunday, no one was left unaccounted for.

Local volunteers and churches have stepped in to provide shelter to displaced Iowans. Ayala praised the community for its togetherness but urged people to stay away from the damaged sites to give space to those who had lost loved ones or their homes.

“We’re a small community, but we take care of each other,” Ayala said. “We’ve had many volunteers coming in to help us. They’re caring. And we’re going to rebuild, but we need time to get together and heal.”

The tornado was spotted by the weather observer at Des Moines International Airport, where all air traffic was briefly halted and travelers were evacuated to underground shelters. The storms left thousands of residents without power late Saturday.

Iowa Gov. Kim Reynolds (R) issued a disaster proclamation for the area Saturday evening to divert state resources to the cleanup and recovery efforts. “Our hearts go out to all those affected by the deadly storms that tore through our state today,” she said.

“Kevin and I join with Iowans in prayer for those that lost their lives and those injured. Our hearts ache during this time, but I know Iowans will step up and come together to help in this time of need. They already are,” Reynolds added.

Large hail and winds topping 80 mph accompanied the severe weather outbreak, which also affected northern Missouri, northern Illinois, southern Wisconsin, northern Indiana and western Ohio, before thunderstorms faded away overnight. Another round of severe thunderstorms, including the possibility of tornadoes, is possible Sunday from northeast Texas through southern Ohio, with northern Arkansas and southern Missouri most at risk.

How the storms evolved

Saturday featured an environment characterized by extreme amounts of spin, though limited instability, or “juice” for storminess. Southerly winds preceding a zone of low pressure brought temperatures in the 60s and a hint of humidity. While that ordinarily wouldn’t have made for terribly robust storms, the exceptional change of wind speed and direction with height meant any clouds that grew tall enough were subjected to strong amounts of spin.

After a midday round of noisy “appetizer storms,” four supercells rapidly developed in southwestern Iowa east of the Missouri River shortly around 3 p.m. Brief intermittent tornadoes touched down, including near the Iowa town of Emerson in Mills County. Before long, the cells began to merge and interfere with one another despite still producing occasional spinups.

That was when the southernmost storm cell in the line predictably began to intensify. Oftentimes, the southern storm becomes the strongest, as it has no neighbors to the south to interrupt its inflow supply of warm moist air, giving it the fuel necessary to strengthen markedly.

The storm first took on an ominous look as it passed near Corning in Adams County along State Route 34 around 3:45 p.m. when it began exhibiting a “bounded weak echo region,” or doughnut hole, on radar. A void was appearing where rain was unable to fall, commensurate with a strong updraft, potentially tornadic, suspending precipitation. A tornado warning had been in effect. There were multiple reports of a brief tornado touchdown south of Corning.

The storm continued moving northeast as warnings extended into Adams and Adair counties. Shortly after 4 p.m., “a confirmed tornado was located near Green Valley Lake,” warned the Weather Service in Des Moines. It was moving quickly northeast at 45 mph. A “hail spike” signature was observed on radar as the storm passed through Orient, where storm chasers reported hail close to 3 inches in diameter that shattered windshields.

Reports indicated the tornado was still on the ground at 4:10 p.m., at which point a new tornado warning was issued downstream for the town of Winterset. The tornado was still confirmed at 4:25 p.m., indicating it was on the ground either continuously or nearly continuously.

Rotation tightened dramatically just before 4:30 p.m., and the tornado struck Winterset at 4:34 p.m. Southeastern parts of the Des Moines metro area were included in a new tornado warning at 4:34 p.m.

The tornado then passed north of Patterson nearby Frahm Concrete Construction and Lyon Enterprises at 4:55 p.m., crossed Interstate 35 between Bevington and Cumming at 5 p.m. and then strengthened further as it hit Norwalk at 5:08 p.m.

At 5:12 p.m., the tornado hit the Highway 65 Interchange near exit 70 along Southeast 14th street. Neighborhoods just north of the Highway 65-Route 5 split were next at 5:18 p.m., including places such as Avon Lake, the Carlisle Sports Complex and Southeast Army Post Road.

The wedge tornado remained intact as it crossed Highway 163 around 5:30 p.m. before barreling across Interstate 80 at 5:47 p.m. The tornado may have lifted briefly northeast of Newton and northwest of Kellogg around 6 p.m.

Shortly after 6 p.m., multiple reports were received of a “large and extremely dangerous” tornado, and it was probably on the ground between 6:04 p.m. and around 6:30 p.m. as it passed through Poweshiek, Tama, Marshall and Jasper counties. Then the circulation briefly reintensified and touched down again around 6:40 p.m. between Toledo and Elderboro, before the storm finally dissipated.

A number of additional tornadoes, including some that were significant, touched down in southern parts of Iowa, leaving behind major damage. Multiple sets of “twin” tornadoes were observed in Lucas and Wayne counties in south central Iowa.

Event of unusual strength

All told, the tornado that tracked through Winterset was probably on the ground continuously for up to an hour and 40 minutes, assuming it didn’t lift between confirmation near Green Valley Lake and crossing Interstate 80. It probably traveled more than 70 miles. Additional tornadoes were confirmed after the storm passed northeast of Interstate 80, so the “tornado family” may have lasted over two hours.

While wind dynamics were certainly supportive of a higher-end tornado, confidence in that outcome was low due to meager instability present. The National Weather Service Storm Prediction Center had only hoisted a level 2 out of 5 “slight chance” of severe weather, even writing that the risk for significant tornadoes was “low” until the morning of the event, when it upgraded the risk to level 3.

While tornadoes have become common in Iowa through the spring and summer, intense twisters are very unusual this early in the calendar year. Only once before, in January 1967, have tornadoes as strong as the one Saturday affected the state this early in the year. That day, an EF4, two EF3s, and eight EF2 tornadoes swept southeastern Iowa.

Late last year, an unusual surge of late autumn tornadoes also caused a great deal of damage across Iowa. That outbreak in December had more than 60 tornadoes, with 21 rated as EF2, making a daily record for Iowa. The tornadoes in western and central Iowa on that day were the first on record in December. But no twisters in that outbreak were as strong as the one Saturday, which was likely at least an EF3.

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The most recent tornado as intense as the one Saturday struck Iowa on last July. The EF3 tracked over sparsely populated parts of the state, and nobody was killed or injured. Should damage surveys confirm that the latest tornado was stronger than initially estimated, it would be the first EF4 tornado in the state since 2013.

That year, an unusual October outbreak spawned a violent tornado in northwest Iowa. That tornado affected few population centers, and nobody was killed or injured. The Saturday storm brought the first killer tornado in Iowa since May 2019 and the first to kill so many in the state since a disastrous EF5 tornado caused nine fatalities in May 2008.

Sunday storm outlook

Storms are forecast to erupt again Sunday afternoon and night as a new storm system developing in Texas sweeps into the Midwest. The Weather Service has declared a level 3 of 5 “enhanced” risk for severe storms from northern Arkansas to southeast Missouri. A broad level 2 of 5 risk for intense storms covers the surrounding zone from northeast Texas to central Kentucky and includes Little Rock, Memphis and Louisville.

The potential exists “for a few tornadoes and damaging winds,” especially this evening and early overnight across parts of northern Arkansas and southern Missouri,” the Weather Service wrote. A third round of strong to severe storms could develop Monday as the storm system progress east with an elevated risk of severe weather from northern Alabama to West Virginia.

Jason Samenow contributed to this report.

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