This article is missing information about the specific details and damage descriptions of major tornadoes. Please expand the article to include this information. Further details may exist on the talk page.(March 2023)
> $6.88 million (1917 USD); >$164 million (2024 USD)
1Most severe tornado damage; see Fujita scale 2Time from first tornado to last tornado
The tornado outbreak sequence of May 25–June 1, 1917 was an eight-day tornado event, known as a tornado outbreak sequence, that killed at least 383 people, mostly in the Midwestern and parts of the Southeastern United States. It was one of the most intense and longest continuous tornado outbreak sequence on record, with at least 66 tornadoes including 15 that were analyzed to have been violent (F4–F5) based upon reported damage.[nb 1] The deadliest tornado of the entire sequence produced a 155-mile (249 km) track across Illinois, killing 108 people and devastating the towns of Charleston and Mattoon along with small farming communities. Once believed to have traveled 293-mile (472 km) across Illinois and into Indiana, it is now assessed to have been a tornado family of four to eight separate tornadoes.[nb 2] This tornado outbreak is one of only 3 outbreaks to reach the classification of a Super Outbreak, with an Outbreak Intensity Score of 296.
A series of low-pressure areas affected the Central and Eastern United States between May 25 and June 1, 1917. The first of these developed by May 25 east of the Rocky Mountains in eastern Colorado. By 7:00 p.m. CST/0100 UTC that day, it intensified to 29.45 inches of mercury (997.3 mb) with temperatures rising at or above 70 °F (21.1 °C) over most of Kansas. The next day, the low-pressure system deepened further into the morning, eventually centering near Yankton, South Dakota, about 7 a.m. CST/1300 UTC. Upon weakening to about 29.55 inHg (1,000.7 mb) in the evening and centering near Des Moines, Iowa, the low was followed by another surface low which formed over the Texas Panhandle and moved northeast. This second low passed near Oklahoma City, Oklahoma, on the morning of May 27 and approached the St. Louis, Missouri, area in the evening. On May 30, yet another low of about 29.5 inHg (999.0 mb) by 7 p.m. CST/0100 UTC moved northeast from near Concordia, Kansas, to Des Moines.[2]
These numbers are likely gross underestimates. Several of the long-track events listed below are likely to be tornado families, or groups of tornadoes produced by the same storm. Because of insufficient documentation, and lack of a proper storm survey by meteorologists, it is impossible to determine where one tornado ends and another begins in certain cases.[1] Additionally, the book by Grazulis which details the tornadoes of this event only documents "significant" tornadoes, that is, tornadoes which caused fatalities or F2 or greater damage on the Fujita scale. On average, almost 70% of tornadoes are not "significant".[3]
23 deaths — Destroyed 118 buildings, with many swept away. Hardest-hit areas were the southeastern part of Andale (12 deaths) and the southern edge of Sedgwick, where eight people died. Three more died in rural areas near McLain and Elbing. The tornado dissipated northeast of Florence. Average path width was 1,200 yards (0.68 mi) .
3 deaths — Swept away three farmhouses in the Manhattan–Monee area. Later hit near Crete and in northern Crown Point. Hit numerous farms along its path.
4 deaths — Destroyed12 farms and damaged 30 others before lifting. A railroad worker died in a boxcar and 25 other people were injured. Three other people were killed on their farms.
1 death — Destroyed six houses in Missouri and caused one death east of Chester, Illinois. The tornado also destroyed Willisville's business district and unroofed or damaged 20 other houses.
18 deaths — Crossed into Tennessee near Tomato, Arkansas after causing six deaths in nearby tenant houses. The tornado killed seven other people in south Dyersburg, four more people south of Sharon, and one more person at Ore Springs (south of Como). Probably a tornado family that leveled many large homes in Tennessee.
67 deaths — Second-deadliest Kentucky tornado on record (65 deaths in-state), second only to the 1890Louisville tornado (76 deaths). Forty-two people were killed in Fulton County, including 21 in the town of Bondurant.
27 deaths — At least two devastating tornadoes, their paths inseparable, killed nine people in Sayre and 17 others in Bradford. It flattened many small houses and killed an infant in Blount County before dissipating.
10 deaths — Leveled farms and small houses near the Big Piney River, south of Hazleton, and northwest of Lenox. This long-track tornado passed only 5 miles (8.0 km) north of the next tornado path, listed below.
10 deaths — Major tornado or tornado family damaged or destroyed homes in Licking, Ranger, Salem, Eye, and Mineral Point. Most of Mineral Point was damaged with house leveled in the northern part of town.
18 deaths — Simultaneously occurred with the next event, which was 4 miles (6.4 km) to the south before merging near Arab. The northern, stronger tornado damaged Granite Bend and several small communities before destroying Dongola and south Zalma. It caused significant F4 damage near Dongola and Zalma.
8 deaths — Merged with the F4 tornado near Arab. The tornado passed south of Taskee and leveled two houses south of Chaonia Landing. The path widened to 1.5 miles (2.4 km) near Arab.
Moved from Lawrenceton into Illinois. In Missouri, the tornado destroyed four houses along with a church, a parsonage, and a blacksmith shop. It caused only minor damage in Illinois.
14 deaths— A tornado destroyed about 200 houses, some of them well-built, two-story structures. Losses reached $200,000. One book from Coalgate was found 40 miles (64 km) away at McAlester State Prison.
This devastating and long-tracked event first began before noon CST in eastern Missouri,[4] where significant hail was reported,[6] then crossed the Mississippi River into Illinois near Pleasant Hill.[5] These two towns were probably hit by two separate, weak tornadoes which formed from the same thunderstorm, but intense tornado damage only began 2 miles (3.2 km) east of Nebo, Illinois.[7] From there, moving east at about 40 miles per hour (64 km/h),[2][5] the first violent member of the event moved into White Hall, hitting farms and injuring six people[6] before weakening and dissipating.[7] Another tornado probably developed over Modesto, 22 miles (35 km) to the east.[6] In Modesto, the tornado destroyed 30 homes and damaged 35 others, with three deaths, 16 injuries, and $120,000 damage reported. Over the next 50 miles (80 km), the tornado either weakened or lifted before touching down again at Dunkel, destroying many homes and barns,[6] and continuing into Westervelt.[7] It destroyed 10 homes and killed four people in Westervelt, but much of the damage was due to hail. Rural areas between Dunkel and Westervelt reportedly received severe damage and reported one death.[6]
After hitting Westervelt, the tornado weakened and probably lifted before reforming and re-intensifying[7] over southern Moultrie County.[6] The new tornado then passed directly through the northern half of Mattoon, causing F4 damage and "near-total destruction" in its path.[7] It destroyed 496 homes, damaged 284, and killed at least 53 people in Mattoon; in the hardest-hit areas, few walls were left standing and only small debris remained.[6] Total damage in Mattoon reached $1.2 million.[7] Between Mattoon and Charleston, a distance of 11 miles (18 km), all farms registered damage and often lost buildings. Entering Charleston, the tornado produced less severe damage than in Mattoon, perhaps due to better construction,[6] but at least 220 homes were still destroyed, 265 badly damaged,[6] 38 people killed, and $780,000 damage caused.[7] The tornado then continued beyond Charleston, causing two final deaths at Embarrass before lifting, though weather officials in 1917 believed that the tornado had continued into Indiana.[6]
At one time, this series of tornadoes was considered a single tornado.[2] Lasting seven hours and 40 minutes and covering 293-mile (472 km), it is now generally believed to have been a family of at least four, and possibly eight or more, distinct tornadoes, with either short breaks in the damage path or sections of straight-line wind damage connecting the tornado paths.[7] Debris such as mail, wallpaper, and parts of books was carried 70 miles (110 km) northeast of the parent supercell.[5] In 1917, the tornado was also believed to have produced winds up to 400 miles per hour (640 km/h),[5] though more recent studies have determined that tornadoes only produce winds up to about 300 miles per hour (480 km/h).[8]
^ abcdeCarey, J. P. (August 1917). "The Central Illinois Tornado of May 26, 1917". Geographical Review. 4 (2). American Geographical Society: 122–130. doi:10.2307/207291. JSTOR207291.
^ abcdefghijklmRoot, Clarence J. (May 1917). "The tornadoes of May 26th and 27th, 1917". Climatological Data. 21. United States Weather Bureau: 40.
^An outbreak is generally defined as a group of at least six tornadoes (the number sometimes varies slightly according to local climatology) with no more than a six-hour gap between individual tornadoes. An outbreak sequence, prior to (after) modern records that began in 1950, is defined as, at most, two (one) consecutive days without at least one significant (F2 or stronger) tornado.[1]