This page documents notable tornadoes and tornado outbreaks worldwide in 1973, but mostly features events in the United States. According to tornado researcher Thomas P. Grazulis, documentation of tornadoes outside the United States was historically less exhaustive, owing to the lack of monitors in many nations and, in some cases, to internal political controls on public information. Most countries only recorded tornadoes that produced severe damage or loss of life. Consequently, available documentation in 1973 mainly covered the United States. On average, most recorded tornadoes, including the vast majority of significant—F2 or stronger—tornadoes, form in the U.S., although as many as 500 may take place internationally. Some locations, like Bangladesh, are as prone to violent tornadoes as the U.S., meaning F4 or greater events on the Fujita scale.
Historically, the number of tornadoes globally and in the United States was and is likely underrepresented: research by Grazulis on annual tornado activity suggests that, as of 2001, only 53% of yearly U.S. tornadoes were officially recorded. Significant low biases in U.S. tornado counts likely occurred through the early 1990s, when advanced NEXRAD was first installed and the National Weather Service began comprehensively verifying tornado occurrences. Owing to increases in storm spotters, the number of tornadoes in the U.S. reached new heights in the early 1970s. 1973 was the first year in which more than 1,000 tornadoes were verified in the United States. The long-term annual mean for the U.S. is roughly 1,300 tornadoes each year, though Grazulis estimates that the real total may be close to 1,800. Despite having the highest annual total in the nation to date, 1973 failed to establish records in terms of significant or killer tornadoes—several earlier years had already done so.
Notable scientific milestones toward understanding the life cycle of tornadoes occurred in Oklahoma on May 24, 1973, when researchers exploited primitive Doppler weather radar, then under development by the National Severe Storms Laboratory (NSSL), to examine a tornado vortex signature, or TVS, for the first time in history. The scientists, in one of the earliest successful cases of storm chasing, were able to study the evolution of a violent tornado near Union City, and to generate clear visual photography of its entire life cycle, from birth to decay. The successful deployment of Doppler weather radar to detect tornado formation also pointed the way to the development of a nationwide Doppler radar system, and helped precipitate funding for studies on tornadogenesis.
Synopsis
At the beginning of the year, one of the strongest El Niño episodes since 1950, as defined by sea surface temperatures, was in progress but gradually diminishing, according to the Oceanic Niño Index (ONI). Peak trimonthly anomalies, measured in moving averages, were +1.7 °C above normal for the period December–February 1972 – 1973. The month of January featured clusters of tornado activity along the Gulf Coast, primarily in Texas and Louisiana, as well as part of the Florida peninsula—a pattern not inconsistent with that of El Niño winters in general. The deadliest and strongest tornado of the month was an F3 that struck Caldwell Parish, Louisiana, on January 18, killing one person and injuring two others. It was part of a larger outbreak on the same date that spawned five other significant tornadoes near the Gulf Coast, with 20 total injuries. A smaller outbreak affected Central Florida ten days later, causing damaging F2 tornadoes in the Campbell–Orlando area, with 24 injuries. February featured much less activity, with 10 confirmed tornadoes compared to 33 in January, and no destructive or deadly tornadoes occurred. Outside the U.S., a catastrophic tornado, believed to be an F5, ravaged a small town in Argentina on January 10, causing more than 50 deaths.
Intense tornado activity increased significantly across the U.S. in March, when the nation's first violent tornadoes of the year touched down in Texas and South Carolina. There were 17 deaths and 300 injuries by the end of the month, largely due to two major tornado outbreaks, and tornadoes occurred as far north as Kansas and Michigan. On March 10, an overnight outbreak concentrated in Texas produced a killer F4 tornado that devastated the small town of Hubbard, killing six people and injuring 77. On March 31, another outbreak spawned a long-lived supercell that tracked through northern Georgia, causing what was officially that state's costliest natural disaster at the time, with prolific losses from a tornado centered in and near Conyers–Athens; damages reportedly reached $113 million in 1973 dollars. Despite the damage, the tornado was of only F2 intensity, and just two deaths were attributed to the tornado, with about 100 injuries. On the same date, a separate tornado in western South Carolina attained F4 strength, killing seven people and injuring 30. In all, 80 tornadoes struck the U.S. in the month of March, 39 of which were F2 or greater.
The month of April was even more active, with 150 tornadoes and 73 F2+ events. The highest concentration of significant tornadoes was in Missouri, where 17 F2+ events occurred. The deadliest tornado of the month was a massive F4 on April 15 that produced intense damage to vehicles and an airport near Pearsall, Texas, killing five people and injuring 12. All of the dead were riding in vehicles, one of which contained eight occupants, mostly Mexicans. The tornado struck two cars traveling on Interstate 35 and lofted them into fields, where they were mangled so badly as to be unidentifiable as vehicles. On the same day, an F3 tornado near Plainview affected Interstate 27 and killed two people, one of whom was yet again inside a car: a monitor working for REACT was positioning himself when the tornado hurled his vehicle hundreds of yards. The latter part of April was extremely active, with a major tornado outbreak sequence on April 19–21 and smaller outbreaks on several other days. The period April 17–28 featured tornadoes on 11 consecutive days. The state of Missouri was hardest hit, with three F4 tornadoes each on April 19–21. There were two deaths during this period, one each in Missouri and Arkansas.
The following month, May, was the deadliest month of the year in the U.S., with 35 fatalities from tornadoes—22 of which took place in a three-day span on May 26–29. The nation's only F5 tornado of the year struck near Valley Mills, Texas, on May 6, where it swept away a few barns, leaving little debris on the foundations. Engineers assigned an F5 rating to the tornado because it lofted a pickup truck for a considerable distance. An outbreak over Ohio on May 10 included an F3 tornado that flattened mobile homes in three trailer courts near Willard, inflicting six deaths and 100 injuries. Deadly F4 tornadoes killed a combined seven people in Oklahoma on May 24 and 26, respectively, with significant impacts to the community of Keefton. An outbreak sequence produced continuous tornado activity from May 26–29, with no gap between tornadoes exceeding six hours. A destructive nighttime tornado, or series of tornadoes, ravaged Jonesboro, Arkansas, on May 26, injuring nearly 300 people, but surprisingly with only three deaths. The next day, a long-tracked, violent tornado crossed almost of central Alabama, obliterating most of the town of Brent, injuring about 200 people, and killing seven.
The remainder of the year featured a rare F4 tornado in New England that struck along the New York/Massachusetts state line on August 28, killing four people, injuring 36, and devastating a large truck stop in West Stockbridge, Massachusetts. An outbreak sequence consisting of several tornado families hit mainly Kansas and Nebraska on September 24–26, with three deaths and almost 60 injuries. At the end of the year, on December 20, Dade County, Florida, experienced one of its most damaging tornadoes to date when an F2 tornado passed through farmland near Homestead, with $800,000 in contemporary losses. In the United States, 1973 was the most active tornado year up to that time, with over 1,100 confirmed tornadoes. Tornadoes killed 89 people nationwide, which exceeded the annual average of about 60, and there were almost 2,400 injuries. Greg Carbin of the Storm Prediction Center (SPC), upon examining data maintained, concluded that strong El Niño events—as measured by the multivariate ENSO index—may foster better conditions for more tornadoes.
Events
United States yearly total
January
33 tornadoes were confirmed in January in the United States.
January 10 (Argentina)
A large and violent but short-lived tornado caused at least 63 direct deaths and 350 injuries as it devastated the town of San Justo in Santa Fe Province, Argentina. The tornado, which traversed the west side of the town, headed south-southwest for about before dissipating, produced peak winds in excess of , and attained a peak width of over , leaving over 2000 people homeless. The tornado affected 500 homes in its path, many of which were leveled or severely damaged, along with a hotel and a car dealership. A press report indicated that numerous homes were swept clean from their concrete foundations. Reportedly, the tornado hurled dozens of vehicles like "ping-pong balls," including an occupied car that flew through the air, with four fatalities from single family being later found hanged on trees. Several vehicles were thrown for at least and mangled beyond recognition. One vehicle was lofted above the ground and "disintegrated"; its motor was later found embedded in a concrete wall about away. Additionally, a tractor was found in a wooded area from its origin, and immense trees were torn from the ground and thrown. Furthermore, grass was reportedly ripped from the ground and a pond outside of town was sucked dry. The tornado, which was officially rated F5 in 2017, was the most violent ever reported in Argentina and Southern Hemisphere, and caused great economic loss. The economic cost of this disaster was about $60,000.
January 18
An outbreak of 10 tornadoes largely affected the Mississippi Valley on January 18, though scattered activity occurred as far west as the town of Seminole in Oklahoma, where an F2 tornado damaged several structures, vehicles, and electrical wires, injuring four people mildly, as well as toppling trees. There was one deadly tornado in the outbreak: an F3 that touched down near Corey, Louisiana, in Caldwell Parish, and lofted a poorly built tenant home for , causing the death of a young woman and injuring her child and another person. The parent supercell later continued into Richland Parish, with a path length totaling . Another tornado, an F2, struck Tallulah, wrecking a self-service laundry and causing roof damage to five homes, resulting in four minor injuries. The largest number of injuries in a single tornado on January 18 occurred in Mississippi, where an F2 near Stallo flipped trailers and a business, both of which shattered, injuring eight people. Two of the injured were hurled from the structure in which they were standing. In all, the entire outbreak spawned tornadoes as far north as southern Illinois, injured 20 people, and killed one.
January 20–22