Between April 23–30, 1961, a tornado outbreak sequence struck the

Midwest The Midwestern United States (also referred to as the Midwest, the Heartland or the American Midwest) is one of the four census regions defined by the United States Census Bureau. It occupies the northern central part of the United States. It ...

Ohio Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the ...

, and

Mississippi Valley The Mississippi River is the main stem, primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri River, Missouri. From its traditional source of Lake Ita ...

s, and the

Eastern United States The Eastern United States, often abbreviated as simply the East, is a macroregion of the United States located to the east of the Mississippi River. It includes 17–26 states and Washington, D.C., the national capital. As of 2011, the Eastern ...

. Large

hailstorms Hail is a form of solid Precipitation (meteorology), precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailsto ...

accompanied the tornadoes as well and numerous other weather events also occurred. Three people were killed, 38 others were injured and losses totaled $26.810 million (1961 USD). Two additional fatalities also occurred due to flooding and lightning.

Meteorological synopsis

A series of at least two or three disturbances moved over the US over the timespan of nine days, starting with a strong weather system that came out of the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in great-circle distance, straight-line distance from the northernmost part of Western Can ...

on April 22. On April 23, multiple cells impacted the

, with several strong, long-tracked tornadoes being reported, producing several casualties. On April 24, multiple clusters of severe thunderstorms formed over

Oklahoma Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northea ...

as well as South-Central and Southeastern Kansas. These storms produced multiple reports of

wind Wind is the natural movement of atmosphere of Earth, air or other gases relative to a planetary surface, planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heatin ...

and

hail Hail is a form of solid Precipitation (meteorology), precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailsto ...

damage,

power outage A power outage, also called a blackout, a power failure, a power blackout, a power loss, a power cut, or a power out is the complete loss of the electrical power network supply to an end user. There are many causes of power failures in an el ...

funnel cloud A funnel cloud is a funnel-shaped cloud of condensed water droplets, associated with a rotating column of wind and extending from the base of a cloud (usually a cumulonimbus or towering cumulus cloud) but not reaching the ground or a water su ...

s, and a

tornado A tornado is a violently rotating column of air that is in contact with the surface of Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the ...

. The storms congealed into a

squall line A squall line, or quasi-linear convective system (QLCS), is a line of thunderstorms, often forming along or ahead of a cold front. In the early 20th century, the term was used as a synonym for cold front (which often are accompanied by abrupt a ...

that produced additional severe weather and tornadoes along with

flash flooding A flash flood is a rapid flooding of low-lying areas: washes, rivers, dry lakes and depressions. It may be caused by heavy rain associated with a severe thunderstorm, hurricane, or tropical storm, or by meltwater from ice and snow. Flash flo ...

through

Missouri Missouri (''see #Etymology and pronunciation, pronunciation'') is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it border ...

into

West Virginia West Virginia is a mountainous U.S. state, state in the Southern United States, Southern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States.The United States Census Bureau, Census Bureau and the Association of American ...

overnight into April 25. Following the squall line, a massive cluster of severe and tornadic thunderstorms with torrential downpours formed over

Indiana Indiana ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Michigan to the northwest, Michigan to the north and northeast, Ohio to the east, the Ohio River and Kentucky to the s ...

and

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

and trekked eastward, producing massive amounts of damage and numerous casualties. General thunderstorms produced scattered activity during April 26-29 before another outbreak surged through the

Great Plains The Great Plains is a broad expanse of plain, flatland in North America. The region stretches east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. They are the western part of the Interior Plains, which include th ...

on April 30, the final day of the sequence.

Confirmed tornadoes

April 23 event

April 24 event

April 25 event

April 26 event

April 27 event

April 28 event

April 29 event

April 30 event

Marshalltown–Vinton–Center Point–Monticello, Iowa

This large, strong, long-tracked F3 tornado–which was most likely a

tornado family A tornado family is a series of tornadoes spawned by the same supercell thunderstorm. These families form a line of successive or parallel tornado paths and can cover a short span or a vast distance. Tornado families are sometimes mistaken as a si ...

–first touched down in Southern Marshalltown and immediately became strong, damaging numerous structures. The damage to the town alone was estimated at $1 million and eyewitnesses reported that tornado had more than one funnel as it passed through town. From there the tornado moved generally eastward at up to on a discontinuous path that may have included more than one tornado. It first passed south of Garwin before crossing the Hinkle Creek directly into

Garrison A garrison is any body of troops stationed in a particular location, originally to guard it. The term now often applies to certain facilities that constitute a military base or fortified military headquarters. A garrison is usually in a city ...

. It then struck the south side of Vinton before moving directly through Center Point and

Alice Alice may refer to: * Alice (name), most often a feminine given name, but also used as a surname Literature * Alice (''Alice's Adventures in Wonderland''), a character in books by Lewis Carroll * ''Alice'' series, children's and teen books by ...

. After crossing the

Wapsipinicon River The Wapsipinicon River (, locally known as the Wapsi) is a tributary of the Mississippi River, approximately long,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed May 13, 2011 starting ...

and striking the north side of Central City, it crossed Buffalo Creek, striking areas south of Prairiesburg. It was observed with a double funnel again as it passed by

Monticello Monticello ( ) was the primary residence and plantation of Thomas Jefferson, a Founding Father, author of the Declaration of Independence, and the third president of the United States. Jefferson began designing Monticello after inheriting l ...

, one of four times this was reported during the tornado's lifespan. The tornado dissipated shortly after that. The tornado traveled , had a maximum width of , and caused $5 million in damage. One person was killed and 12 others were injured. The tornado was also notable because it was embedded within a massive swath of wind and hail damage that was wide. Wind gust of up to were recorded along with hail up to in diameter. Northwest Jones County saw an excessive amount of hail with up to drifts in some areas.

Lorenzo–Peotone, Illinois/Belshaw–Roselawn, Indiana

This strong, destructive, long-tracked F3 tornado (which was also likely a

) accompanied by a vicious

hailstorm Hail is a form of solid precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailstone. Ice pellets generally fal ...

first touched down over

Lorenzo, Illinois Lorenzo is an unincorporated community and census-designated place (CDP) in Will County, Illinois, United States. It is in the southwest part of the county, in the valley of the Kankakee River. Interstate 55 passes to the east, and the city of ...

. It proceeded east-southeastward, immediately becoming strong and destroying seven homes in the town. It then crossed the

Kankakee River The Kankakee River is a tributary of the Illinois River, approximately long, in the Corn Belt, Central Corn Belt Plains of northwestern Indiana and northeastern Illinois in the United States. At one time, the river drained one of the largest we ...

and passed north of Wilmington, toppling a trailer truck. Passing north of Symerton and south of Wilton Center, the tornado continued to damage numerous homes and farmsteads as it moved through open country, before plowing into Peotone. 600 homes were damaged by both the tornado and the massive hail that fell with it. One hailstone was reportedly in diameter, although this was never verified. The Peotone Airport was hit hard as 21 planes were damaged by hail alone, with most being completely totaled beyond repair. All four injuries from the tornado occurred in Peotone when a house trailer was rolled. The tornado then weakened and may have briefly lifted as it passed halfway between

Beecher Beecher may refer to:__NOTOC__ People *Beecher (surname) Places United States *Beecher, Illinois * Beecher, Michigan, a census-designated place and unincorporated community near Flint * Beecher, Wisconsin, a town * Beecher (community), Wisconsin, ...

and

Polk DNA polymerase kappa is a DNA polymerase that in humans is encoded by the ''POLK'' gene. It is involved in translesion synthesis DNA repair is a collection of processes by which a cell (biology), cell identifies and corrects damage to the ...

before abruptly turning southeastward as it entered

on a non-continuous damage path. Throughout

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

, the tornado injured four and caused $2.5 million in damage. As the tornado touched downed again in Indiana, more large hail began to fall. The tornado passed west of North Hayden located west of

Lowell, Indiana Lowell ( ) is a town in West Creek and Cedar Creek townships, Lake County, Indiana, United States. The population was 10,680 at the 2020 census. History Lowell was platted in 1853. It was named after Lowell, Massachusetts. On June 27, 1868, L ...

before causing the heaviest damage in the state near Belshaw at the intersection of

US 41 U.S. Route 41, also U.S. Highway 41 (US 41), is a major north–south United States Numbered Highway System, United States Numbered Highway that runs from Miami, Florida, to the Upper Peninsula of Michigan. Until 1949, the part i ...

and SR 2. Here the tornado damaged multiple farm buildings and toppled 30 billboards along US 41. Hail up to in diameter and a depth of up to an fell in here and in the nearby town of Schneider, where the hail damage to roofs and windows was the most extensive. The tornado then passed west of Shelby and

Thayer Thayer may refer to: Places ;United States * Thayer, Illinois * Thayer, Indiana * Thayer, Iowa * Thayer, Kansas * Thayer, Michigan * Thayer, Missouri * Thayer, Nebraska *Thayer, West Virginia * Thayer County, Nebraska * Thayer Street, Providence, ...

before dissipating just outside of Roselawn. The tornado did F2 damage at its peak in Indiana with losses totaling $250,000. The tornado traveled , was wide, and caused $2.75 million in damage. There were four injuries.

Marion–Waterloo–Boston, Indiana/Eaton, Ohio

Four funnel clouds consolidated into this long-tracked, violent, skipping multi-vortex F4 tornado–which may have been

of at least two tornadoes. It first touched down in

Shelby County, Indiana Shelby County is a county in the U.S. state of Indiana. As of the 2020 United States census, the population was 45,055. The county seat (and only incorporated city) is Shelbyville. History After the American Revolutionary War established US ...

northwest of Shelbyville along

I-74 Interstate 74 (I-74) is an Interstate Highway in the Midwestern and Southeastern United States. Its western end is at an interchange with I-80 in Davenport, Iowa; the eastern end of its Midwest segment is at an interchange with I-75 ...

and immediately became violent, tossing a loaded truck . It then proceeded east-northeastward at , heavily damaging

Marion Marion or MARION may refer to: Arts and entertainment *Marion (band), a British alternative rock group * ''Marion'' (miniseries), a 1974 miniseries * ''Marion'' (1920 film), an Italian silent film * ''Marion'' (2024 film), a UK short People a ...

and Knighthood Village. A total of 10 homes and 21 barns were destroyed, and 11 other homes were badly damaged. One person was injured and losses totaled $2.5 million in the area. The tornado then continued into rural areas of Rush County, where 15 homes were badly damaged. North of Rushville, multiple trucks were rolled or flipped, injuring three. Homes and buildings south of the town of Gings were also badly damaged and losses in the county reached $2.5 million. In Fayette County, the tornado moved through mostly rural areas before passing through the three-town trio of

Harrisburg Harrisburg ( ; ) is the List of capitals in the United States, capital city of the Commonwealth (U.S. state), U.S. commonwealth of Pennsylvania and the county seat, seat of Dauphin County, Pennsylvania, Dauphin County. With a population of 50, ...

, Huber and

Waterloo Waterloo most commonly refers to: * Battle of Waterloo, 1815 battle where Napoleon's French army was defeated by Anglo-allied and Prussian forces * Waterloo, Belgium Waterloo may also refer to: Other places Australia * Waterloo, New South Wale ...

. Waterloo was the hardest hit as multiple homes and buildings were destroyed. Three homes and two mobile homes were obliterated throughout the county before the tornado clipped the northwest side of Union County, passing south of

Philomath A philomath () is a lover of learning and studying. The term is from Greek (; "beloved", "loving", as in philosophy or philanthropy) and , (, ; "to learn", as in polymath). Philomathy is similar to, but distinguished from, philosophy in that ...

and Abington. Damage in both counties reached $2.5 million. Some of the most extreme damage occurred as the tornado entered Wayne County and struck the town of

Boston Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeas ...

. Two homes and a mobile home were obliterated and three people in one of the homes were injured, one seriously. Heavy damage occurred along the roads heading in and out of town before the tornado moved into

. Losses in Wayne County reached $2.5 million. The tornado then turned almost due east as it moved into rural

Preble County, Ohio Preble County ( ) is a county located in the U.S. state of Ohio. As of the 2020 census, the population was 40,999, down 3.0% from the 2010 census population of 42,270. Its county seat is Eaton. The county was formed on February 15, 1808, fr ...

. By this point, the skipping nature of the tornado became more evident as it remained on the ground for at a time with a width no larger than . Nonetheless, the tornado remained strong to violent. It first struck the town of West Florence, heavily damaging or partially destroying multiple farmhouses and barns. As the tornado entered the west side of Eaton, another farmhouse was obliterated and swept away, although a ring of trees around the home were incredibly left undamaged. A nearby barn was also obliterated and an adjacent housing development of brand new homes was badly damaged. The tornado then weakened, but remained strong as it entered Eaton, damaging a grove of trees as well as the roof of an office buildings and stores. The tornado then weakened further as it continued through the central part of Eaton, causing only light to minor damage to treetops and roofs and breaking windows before finally dissipating on the east side of town. Damage in Ohio reached $2.5 million. The tornado was on the ground for at least 89 minutes, traveled , and was (one source says ) wide. Seven people were injured and losses totaled $12.5 million in damage.

Non-tornadic impacts

Numerous reports of strong winds and large hail were recorded throughout the event. The complex of storms that moved through

on April 25 produced a wind gust southeast of Burtonville. Gigantic hail fell in

on April 30, peaking at southwest of El Reno. Throughout the event there were 11 reports of hail over in diameter and nine report of wind gusts over . Flash flooding was also a major issue throughout the event and one man did drown after being caught flood waters caused by Adens Creek in

. Heavy rainfall also caused flash flooding and numerous accidents in Southeastern Kansas on April 30, injuring one.

Lightning Lightning is a natural phenomenon consisting of electrostatic discharges occurring through the atmosphere between two electrically charged regions. One or both regions are within the atmosphere, with the second region sometimes occurring on ...

was a surprisingly destructive and deadly catalyst during the event. Overnight during April 24-25, multiple lightning strikes across

Southern Michigan Southern Michigan is a loosely defined geographic area of the U.S. state of Michigan. Southern Michigan may be referred to as a sub-region or component area to other regions of the Lower Peninsula of Michigan. It is an area of rolling farmland, ...

triggered several fires that seriously damaged homes, destroyed a barn, and caused power outages in both

Ann Arbor Ann Arbor is a city in Washtenaw County, Michigan, United States, and its county seat. The 2020 United States census, 2020 census recorded its population to be 123,851, making it the List of municipalities in Michigan, fifth-most populous cit ...

and

Flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start ...

. In an extreme case on April 26,

static electricity Static electricity is an imbalance of electric charges within or on the surface of a material. The charge remains until it can move away by an electric current or electrical discharge. The word "static" is used to differentiate it from electric ...

caused by intense lightning strikes caused a premature explosion of a 5-lb. charge of dynamite in a water tunnel that was under construction in Northboro, Massachusetts. One person was killed and 11 others were injured, three seriously, with one man losing his arm. In Northeastern Montana, rain turned to

snow Snow consists of individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes. It consists of frozen crystalline water througho ...

, and high winds from the evening of April 22 into April 23. An all-day

blizzard A blizzard is a severe Winter storm, snowstorm characterized by strong sustained winds and low visibility, lasting for a prolonged period of time—typically at least three or four hours. A ground blizzard is a weather condition where snow th ...

also occurred in Western and Southern North Dakota on April 23, with snow totals reaching as high as . Since it was heavy, wet snow, it froze up on power lines overnight, leading to widespread power outages. High winds on the back side of the first system on April 23 caused heavy damage to crops in Southeastern Wyoming, Northwestern Nebraska, and Northeastern Colorado.

Greeley, Colorado Greeley is the home rule municipality city that is the county seat and the most populous municipality of Weld County, Colorado, United States. The city population was 108,795 at the 2020 United States census, an increase of 17.12% since the ...

was especially hard hit as a factory lost approximately 600 acres of

sugar beets A sugar beet is a plant whose root contains a high concentration of sucrose and that is grown commercially for sugar production. In plant breeding, it is known as the Altissima cultivar group of the common beet (''Beta vulgaris''). Together with ...

Notes

References