|Date of tornado outbreak:||Wednesday, March 18, 1925|
|Maximum rated tornado2:||F5 tornado|
|Tornadoes caused:||9 known|
|Fatalities:||747+ (695+ from one tornado)|
|Areas affected:||Missouri, Illinois, Indiana, Kentucky, Tennessee, Alabama, Kansas, possibly other states|
1Time from first tornado to last tornado
The Great Tri-State Tornado of Wednesday, March 18, 1925, was the deadliest tornado in U.S. history. Inflicting 695 fatalities, the tornado killed more than twice as many as the second deadliest, the 1840 Great Natchez Tornado. The continuous ≥219 mile (≥352 km) track left by the tornado was the longest ever recorded in the world: the tornado crossed from southeastern Missouri, through southern Illinois, then into southwestern Indiana. Although not officially rated by NOAA, it is recognized by most experts (such as Tom Grazulis) as an F5 tornado, the maximal damage rating issued on the Fujita scale
1925 Tri-State Outbreak 
The tornado was part of a larger tornado outbreak with several other destructive tornadoes the same day in Tennessee, Kentucky, and Indiana, as well as significant tornadoes in Alabama and Kansas. Including additional tornadoes that day, at least 747 people were killed and 2,298 were injured. This makes the Tri-State Outbreak the deadliest tornado outbreak, March 18 the deadliest tornado day, and 1925 the deadliest tornado year in U.S. history. There were undoubtedly other less impactful tornadoes, the occurrences of which have been lost to history.
|List of significant tornadoes — March 18, 1925|
|F2||Dearing||Montgomery||0510||unknown||Homes and gas station damaged at and around Dearing.|
|F5||NNW of Ellington, Missouri to 10 mi (16 km) NE of Princeton, Indiana||Reynolds; Iron; Madison; Bollinger; Cape Girardeau; Perry; Jackson, IL; Williamson, IL; Franklin, IL; Hamilton, IL; White, IL; Posey, IN; Gibson, IN; Pike, IN||1301||234 miles (377 km)||695 deaths - Deadliest single tornado in US history - See section on this tornado|
|F2||Littleville||Colbert||1642||12 miles (19 km)||1 death - Tornado moved northeast in Littleville where damage and casualties at a gas station, homes, and a store occurred; 60 yd (55 m) average path width. 12 others were injured.|
|F4||Near Buck Lodge, Tennessee to Beaumont, Kentucky||Sumner; Allen, KY; Barren, KY; Monroe, KY;, Metcalfe, KY||1700||60 miles (97 km)||39 deaths - Moved ENE from 8 mi (13 km) north of Gallatin, Tennessee, homes leveled in many communities, possibly a tornado family; 400 yd (370 m) average path width. 95 others were injured.|
|F3||Kirkland||Williamson; Rutherford||1745||20 miles (32 km)||1 death - Major damage to homes in Kirkland incurring all casualties; 200 yd (185 m) average path width. Nine others were injured.|
|F3||Near Unionville to 2 mi (3 km) NE of Fosterville||Bedford; Rutherford||1810||12 miles (19 km)||2 deaths - Moved ENE, at least 10 homes destroyed; 300 yd (275 m) average path width. 15 others were injured.|
|F4||Mauckport, Indiana to southern border of Louisville, Kentucky||Harrison; Jefferson, KY||1715||18 miles (29 km)||4 deaths - Up to mile (1.6 km) wide, moved ENE, swept away entire farms near Laconia and Elizabeth, Indiana before ending just south of Louisville, Kentucky; 1200 yd (1100 m) average path width. 60 others were injured|
|F3||Louisville to near Pewee Valley||Jefferson; Oldham||1800||10 miles (16 km)||≥3 deaths - Moved NE from east edge of Louisville to near Pewee Valley; at least 12 homes destroyed. 40 others were injured, and the death toll may have been higher.|
|F3||Western Marion County to Lexington, Kentucky area||Marion; Washington; Mercer; Jessamine; Fayette; Bourbon||1830||60 miles (97 km)||2 deaths - Tornado family moved ENE from western Marion County, passing near Springfield, and ending past Lexington; 300 yd (275 m) average path width. 40 others were injured.|
Tri-State Tornado 
One tornado or a series? 
There has been uncertainty as to whether the event was one continuous tornado or a tornado family. The sparse quality of tornado data because of distance in the past and the lack of other tornadoes approaching this path length and duration raised doubts; and meteorological theory on tornadoes and supercell morphology suggested such duration was exceedingly improbable. In fact, several other historically very long track tornadoes were subsequently found to be tornado families, (notably the Woodward, Oklahoma tornado family of April 1947 and the Charleston-Mattoon, Illinois tornado family of May 1917) although in the past several years some very long track tornadoes and supercells occurred. Ongoing new research, however, finds no break in the path and also that the tornado began approximately 15 miles (24 km) farther west than previously thought, bringing the total path length to around 234 miles (377 km).
Storm track 
The vortex was first sighted at around 1:01 p.m., north-northwest of Ellington, Missouri. The tornado sped to the northeast, killing two and causing $500,000 worth of property damage and the near annihilation of Annapolis, then struck the mining town of Leadanna. In Bollinger County, 32 children were injured when two schools were damaged. The tornado carried sheets of iron as far as 50 miles (80 km) away. Redford, Cornwall, Biehle, and Frohna also were hit by the tornado. At least 11 died altogether in Missouri.
The tornado crossed the Mississippi River into southern Illinois, hitting the town of Gorham, at 2:30 p.m., essentially obliterating the entire town, killing 34. Continuing to the northeast at an average speed of 62 miles per hour (100 km/h) (and up to 73 miles per hour (117 km/h)), the tornado cut a swath almost 1 mile (1.6 km) wide through Murphysboro, De Soto, Hurst-Bush, and West Frankfort. Also afflicted were Zeigler, Eighteen, and Maunie. Within 40 minutes, 541 lives were lost and 1,423 were seriously injured. The village of Parrish was completely destroyed, killing 22. In Murphysboro, 234 were killed, the most in a single city in U.S. history. The tornado proceeded to decimate rural areas across Hamilton and White Counties, claiming 65 more residents.
Crossing the Wabash River into Indiana, the tornado struck and nearly totally demolished Griffin, devastated rural areas, impacted Owensville, then roared into Princeton, destroying half the town. The tornado traveled another 10 miles (16 km) to the northeast before finally dissipating at about 4:30 p.m. around 3 miles (4.8 km) southwest of Petersburg. In Indiana, at least 71 perished.
In all, at least 695 died and 2,027 were injured, the majority in southern Illinois. Three states, thirteen counties, and more than nineteen communities, four of which were effectively effaced (several of these and other rural areas never recovered), were in the path of the record 3.5 hour duration tornado. Approximately 15,000 homes were destroyed by the Tri-State Tornado. Total damage was estimated at $16.5 million; adjusted for wealth and inflation the toll is approximately $1.4 billion (1997 USD), surpassed in history (through 2010) only by two extremely destructive tornadoes in the City of St. Louis in 1896 and 1927. These three events in terms of destruction, inferred by normalized monetary losses, are by far the most destructive (expensive) tornadoes ever in the United States.
Nine schools across three states were destroyed in which 69 students were killed. More schools were destroyed and more students killed (as well as the single school record of 33 deaths in De Soto, Illinois) than in any other tornado in U.S. history.
The unusual appearance, due to its size and the probable low cloud base of its parent thunderstorm, of the very swift moving tornado, frequently described by the witnesses as an amorphous rolling fog or boiling clouds on the ground, fooled normally weather wise farm owners (in addition to people in general) who did not sense the danger until the storm was upon them. The condensation funnel itself was also reportedly sometimes wrapped in dust and debris as to make it obscured and less recognizable.
The tornado was often accompanied by extreme downburst winds throughout the entirety of its course; the tornado and accompanying downburst increased the width of damage from an average of 0.75 miles (1.21 km) (though at times over 1 mile (1.6 km) wide) to an area 3 miles (4.8 km) wide at times.
In addition to the dead and injured, thousands were left without shelter or food. Fires erupted, exacerbating the damage. Looting and theft, notably of the property of the dead, was reported. Recovery was generally slow with the event leaving a lasting blow to the region.
See also 
|Wikimedia Commons has media related to: Tri-State Tornado|
- Christine Gibson "Our 10 Greatest Natural Disasters," American Heritage, Aug./Sept. 2006.
- Grazulis, Thomas P. (July 1993). Significant Tornadoes 1680-1991: A Chronology and Analysis of Events. St. Johnsbury, VT: The Tornado Project of Environmental Films. ISBN 1-879362-03-1.
- Grazulis, Thomas P. (2001). F5/F6 Tornadoes. St. Johnsbury, VT: The Tornado Project of Environmental Films.
- 2011 tornado information
- NOAA Photo Library
- Morris, Sean (May 23, 2011). "Up until 1940s, Americans didn't even get tornado forecasts". CNN. Retrieved 2011-05-24. "Thus, experts now don't know whether the 1925 Tri-State tornado — which killed about 695 people when it tore through Missouri, Illinois and Indiana — was actually a single funnel or many, which is why it isn't officially considered the deadliest single tornado."
- Doswell, Charles A., III; D. W. Burgess (1988). "On Some Issues of United States Tornado Climatology". Mon. Wea. Rev. 116 (2): 495–501. doi:10.1175/1520-0493(1988)116<0495:OSIOUS>2.0.CO;2.
- Doswell, Charles A., III; C. Crisp, R.A. Maddox, J. Hart, R.H. Johns, M.S. Gilmore, D.W. Burgess, Steve Piltz. "The Tri-State Tornado of 18 March 1925 Reanalysis Project: Preliminary Results" (Powerpoint Presentation). Archived from the original on 2008-03-07. Retrieved 2008-03-08.
- "Tornado Track". 1925 Tri-State Tornado: A Look Back. NWS Paducah. Retrieved 2013-04-01.
- "Startling Statistics". 1925 Tri-State Tornado: A Look Back. NWS Paducah. Retrieved 2013-04-01.
- Brooks, Harold E.; C.A. Doswell (February 2001). "Normalized Damage from Major Tornadoes in the United States: 1890–1999". Wea. Forecast. 16 (1): 168–76. doi:10.1175/1520-0434(2001)016<0168:NDFMTI>2.0.CO;2.
- Maddox, Robert A.; M. S. Gilmore, C. A. Doswell III, R. H. Johns, C. A. Crisp, D. W. Burgess, J. A. Hart, S. F. Piltz (2013). "Meteorological Analyses of the Tri-State Tornado Event of March 1925". E-Journal of Severe Storms Meteorology 8 (1).
- Burgess, Donald W. (2006-11-10). "The Tri-State Tornado of 18 March 1925, Part I: Re-examination of the damage path". 23rd Conf. Severe Local Storms. St. Louis, MO: American Meteorological Society. http://ams.confex.com/ams/23SLS/techprogram/paper_115466.htm.
- Maddox, Robert A.; M.S. Gilmore, C. Crisp, J.A. Hart, C.A. Doswell, D.W. Burgess (2006-11-10). "The Tri-State Tornado of 18 March 1925. Part II: Re-examination of the weather conditions supporting the parent storm". 23rd Conf. Severe Local Storms. St. Louis, MO: American Meteorological Society. http://ams.confex.com/ams/23SLS/techprogram/paper_115418.htm.
- Grazulis, Thomas P. (2001). The Tornado: Nature's Ultimate Windstorm. Norman, OK: University of Oklahoma Press. ISBN 0-8061-3258-2.
- Wilson, John W.; Stanley A. Changnon, Jr. (1971). Illinois Tornadoes (Circular 103). Urbana-Champaign, IL: Illinois State Water Survey.
- Changnon, S.A.; R.G. Semonin (1966). "A great tornado disaster". Weatherwise 19 (2): 56–65. doi:10.1080/00431672.1966.9930508.
- Flora, Snowden D. (1953). Tornadoes of the United States. Norman, OK: University of Oklahoma Press. ISBN 978-0806102627.
- Root, Clarence J. (February 1926). "Some Outstanding Tornadoes". Mon. Wea. Rev. 54 (2): 58–60. doi:10.1175/1520-0493(1926)54<58:SOT>2.0.CO;2.
- Root, C.J.; W.E. Barron (1925). "The Tri-State tornado of March 18, 1925". Climatological Data, Illinois Section (U.S. Weather Bureau): 12a–12d.
- Henry, Alfred J. (April 1925). "The Tornadoes of March 18, 1925". Mon. Wea. Rev. 53 (4): 141–5. doi:10.1175/1520-0493(1925)53<141:TTOM>2.0.CO;2.
- "Severe Local Hail and Wind Storms, March, 1925". Mon. Wea. Rev. (U.S. Weather Bureau) 53 (3): 130. March 1925. doi:10.1175/1520-0493(1925)53<130:SLHAWS>2.0.CO;2.
- The Tri-State Tornado (The Tornado Project)
- 1925 Tri-State Tornado (NWS Paducah, KY)
- The Weather Channel's Storm of the Century list – #7 The Tri-State Tornado
- The Great Tri-State Tornado (RootsWeb Genealogy)
- Newspaper Coverage of the Tri-State Tornado Ravage of Murphysboro (NIU Library)
- Tri-State Tornado: Missouri, Illinois, Indiana, March 1925 (Popular Mechanics)
- The 1925 Tornado (Carolyar.com Genealogy)
- Felknor, Peter S. (1992). The Tri-State Tornado: The Story of America's Greatest Tornado Disaster. Ames, IA: Iowa State University Press. ISBN 0-8138-0623-2.
- Akin, Wallace E. (2002). The Forgotten Storm: The Great Tri-state Tornado of 1925. Guilford, CT: Lyons Press. ISBN 1-58574-607-X.
- Mason, Angela (2011). Death Rides the Sky: The Story of the 1925 Tri-State Tornado. Rockford, IL: Black Oak Media. ISBN 978-1-61876-001-2.
- Johns, Bob (2012). The 1925 Tri-State Tornado's Devastation In Franklin County, Hamilton County, And White County, Illinois. Bloomington, IN: AuthorHouse. ISBN 978-1468560961.
|10 deadliest American tornadoes|
|1||"Tri-State" (Missouri, Illinois and Indiana)||March 18, 1925||695|
|2||Natchez, Mississippi||May 7, 1840||317|
|3||St. Louis, Missouri and East St. Louis, Illinois||May 27, 1896||255|
|4||Tupelo, Mississippi||April 5, 1936||216|
|5||Gainesville, Georgia||April 5, 1936||203|
|6||Woodward, Oklahoma||April 9, 1947||181|
|7||Joplin, Missouri||May 22, 2011||158|
|8||Amite, Louisiana and Purvis, Mississippi||April 24, 1908||143|
|9||New Richmond, Wisconsin||June 12, 1899||117|
||June 8, 1953
Source: Storm Prediction Center