A HISTORICAL AND STATISTICAL COMPARISON OF "TORNADO ALLEY" TO "DIXIE ALLEY" John P. Gagan National Weather Service Springfield,Alan Gerard Missouri Jackson, Mississippi National Weather Service John Gordon Louisville, Kentucky National Weather Service Abstract describe various parts of the United States that are perceived to have a high incidence of tornado The media and public frequently use the term “tornado alley,” an unofficial term which is used to occurrence. This paper examined the history of the term “Tornado Alley,” as well as the lesser known term “Dixie Alley.” A basic statistical analysis of the temporal and spatial occurrence of tornadoes and tornado-related casualties was done in each of these areas, both long term and in the recent years following the modernization of the National Weather Service. Corresponding Author: Alan Gerard NationalJackson, Weather MS 39232 Service email:234 [email protected] Service Drive Gagan, et al. 1. History and Terminology • “States included in ‘Tornado Alley’ are Texas, a. Tornado Illinois, Indiana, and Missouri.” • Colorado, Kansas, Nebraska, Oklahoma, Arkansas, phenomena and certainly one of the most destructive. southern“An L-shape Oklahoma region, whichand then stretches over Arkansas from western and Tornadoes are one of thetornado most talked about weather LouisianaIowa down to through southeastern Nebraska Mississippi.” and Kansas to The history of the word took several twists Some publications that address “tornado alley” included: thunderstorm,before it landed tronada with its, and current then turnedmeaning into in ternadothe United by EnglishStates. sailorsUltimately, in the it comes1500s fromto mean the “aSpanish violent word tropical for • tornadoes occur most often is in an L-shaped “The primary area of the U.S. in which significant storm.” In pop-culture, movies such as “The Wizard of Oz” in 1939, “Mr. and Mrs. Bridge” in 1990, and “Twister” (Concannonregion from Iowaet al. to2000) Oklahoma to Mississippi, in 1996 have certainly increased the public’s awareness. • with the highest threat in Oklahoma.” KansasPublic awareness turnpike bridge has been on fueled26 April with 1991, impressive the 3 May tornado 1999 videovideos, from including the Moore, a television Oklahoma crew F5 hiding tornado, underneath and the 24 a separately.“Texas, Oklahoma, This region Kansas, essentially Nebraska, contains Iowa, the Missouri, Arkansas, Louisiana were analyzed most prevalent.” (Schaefer and Tatom1999) June 2003 National Geographic video from inside an F3 proverbial ‘tornado alley’ where tornadoes are b.tornado “Tornado near Alley” Manchester, South Dakota. Historically, the term “Tornado Alley” has been used loosely, and the locations indicated are often based on term “Tornado Alley.” Generally speaking, this is an area Many Americans are familiar with the widely used personal perception rather than scientific data (Grazulis thought of as the location for peak tornado occurrence in 1993). The authors personally spoke to Dr. Charles of the Great Plains and Midwest which is commonly Doswell III and Dr. Howard Bluestein from the University of Oklahoma, Tom Grazulis from The Tornado Project, the United States. However, a less commonly known term retired Storm Prediction Center (SPC) Director Dr. Joe is that of “Dixie Alley.” This generally refers to that part of Schaefer, retired SPC Science and Operations Officer the southeastern United States which is prone to tornado Bob Johns, retired National Severe Storms Forecast development. This manuscript will take an in depth look Center (NSSFC) Director Fred Ostby, and former NSSFC at theIf you similarities use any of and the populardifferences internet between search “Tornado engines aforementionedDirector Allen Pearson. referenced Nobody Snoden could Flora’s provide 1954 a definitive tornado Alley” and “Dixie Alley.” answer to the origin of “Tornado Alley.” Most of the Flora’s manuscript. The authors conducted a thorough orand so, type the in location “tornado for alley tornado location”, alley variesyou will greatly. come Someup with of climatology, although we could not locate a reference in theseover 400,000 include: hits. Of the first 100 internet search results every decade from the 1950s through today. This included literary search which entailed numerous papers from • several papers from Snoden Flora, Dr. Theodore Fujita, “Region in the middle of the United States where and TheDr. Howardonly “tornado Bluestein alley” which reference offered that no the insights authors to • “Mostmore tornadoes tornadoes occur in the than United anywhere States form else in anthe definitive location or origin. Take-off, the Tinker, areaworld.” called ‘Tornado Alley.’ This area includes Januarycould obtain 16, 1953 was from[Available an article online in at: • OK Air Force Base (AFB) newspaper, which]. appeared The article on fromparts north-centralof Texas, Oklahoma, Texas through Kansas, centraland Nebraska.” http://www.nssl. “By most definitions, ‘Tornado Alley’ extends noaa.gov/GoldenAnniversary/awards.html stated: “On Feb 15, 1952, Fawbush and Miller set up a new dryOklahoma, air collide Kansas, time andafter Nebraska time.” into the extendingproject called, from ‘Tornado Lubbock, Alley,’ Texas into whichEastern a Coloradoconcentrated and • “TheDakotas, United the Statesnorth-south ‘Tornado line Alley’ where stretches moist and from study of severe weather activity was made over an area Lubbock, Texas to Enid, Oklahoma, and the second from northeast Kansas.” Nebraska. This was done in stages, the first being from northwest Texas across Oklahoma and through 146 National Weather Digest Enid, Oklahoma to the Nebraska line.” A Historical and Statistical Comparison of "Tornado Alley" to "Dixie Alley" c. “Dixie Alley” perceptions. Tornado Alley, hereafter referred to as the Kansas and Oklahoma, and a large portion of northern the authors once again consulted those tornado experts andPlains central Tornado Texas Alley (Fig. 1).(PTA), includes all of Nebraska, previouslyRegarding cited, the andorigin researched and location numerous of “Dixie previous Alley,” been an idea cultivated through the observations of The existence of a Dixie Tornado Alley (DTA) has publications. Most experts referred the authors to Dr. Harold Brooks, but Dr. Brooks told us explicitly that he meteorological professionals who have lived in the Pearson.did not coin Mr. Pearsonthe phrase. explained The only that source he personally that knew coined the southern states and those with severe weather forecasting origin of “Dixie Alley” was former NSSFC Director Allen severeexperience. thunderstorm The first climatology. statistical analysis A higher suggesting frequency the of of 21 February 1971. This event had 10 long-track validity of a DTA was provided by Brooks et al. (2003) tornadoesthe phrase thatafter resulted working inthe 121 Mississippi deaths and Delta over outbreak 1,500 tornadoes was located from Louisiana through much of Mississippi and Alabama, when accounting for the mean injuries. Pearson compared that event with the Arkansas- thenumber frequency of days of withlong-track tornadoes (path from length October greater through than Tennessee outbreak of 21-22 March 1952, where 28 25December. miles) violent Broyles tornadoes and Crosbie (rated F3(2004) to F5) investigated across the tornadoes struck, killing over 200 people. Both events were in the south, and PearsonUSA Todaycoined Weather the phrase [Available “Dixie onlineAlley” inat: 1971. One of the few websites defining Dixie inUnited central States Mississippi from 1880 andto 2003. an area They extending discovered from that storms/1999/ndstue09.htmAlley was from an article in two of the most prominent tornado alleys were located http://www.usatoday.com/weather/tornado/ from northeast Texas to northern] which Alabama, stated: then“A skipsthird proposedwestern Tennessee by this investigation into northern includes portions all of of Mississippi Arkansas, tornado focus is the so-called ‘Dixie Alley’, which runs and Alabama. With these discoveries in mind, the DTA Carolina.” Tennessee, and northern and central Georgia (Fig. 1). over the southern Appalachians and reforms in North Louisiana, Mississippi and Alabama, western and central b. Methodology Since there was such limitedSignificant formal Tornadoes, documentation, 1680- 1991it was compendium, difficult to compare there is morethe two than tornado one tornado alleys. alley. As “AnyGrazulis area (1993)that seems stated to experience in above average tornado frequency is eventually labeled a ‘tornado alley.’ There are databaseTornado [Available data for online both at: the PTA and DTA were gathered from]. This the database Storm Prediction provides detail Center’s ranging ONETOR from tornado alleys across the United States based on a long the physical attributes of eachhttp://www.spc.noaa.gov/ tornado (e.g., location, dozens of such regions.” There is also evidence of smaller wcm/#data track F3 to F5 tornado climatology study from 1880 to damage rating, path length and width), to the effects of statistical2003 (Broyles analysis and Crosbieof the frequency 2004). This of papertornadoes will bridgein the the gap between perception and reality by offering a basic “Tornado“Dixie Alley.” Alley.” In an effort to support the validity of a “Dixie Alley,” these statistics will be compared to those from 2. Tornado Alley and Dixie Alley – A Historical Study a. Background accepted by the meteorological community for decades, thoughThe asexistence discussed