[11] 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.

[10][13] 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.

[15] 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.

[16] 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.

[16][19] On March 31, another outbreak spawned a long-lived supercell that tracked through northern Georgia, causing what was officially[nb 2] 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.

[16] 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.

[25] 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.

[16][28] The next day, a long-tracked, violent tornado crossed almost 140 mi (230 km) of central Alabama, obliterating most of the town of Brent, injuring about 200 people, and killing seven.

[28] 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.

[16] 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.

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.

Reportedly, the tornado hurled dozens of vehicles like "ping-pong balls,"[32] including an occupied car that flew 30 ft (9.1 m) through the air, with four fatalities from victims who fell to the ground.

[32] Additionally, a 10 tonnes (10,000 kg) tractor was found in a wooded area 300 m (330 yd) from its origin,[32] and immense trees were torn from the ground and thrown.

[35][36] 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 100 yards (91 m), causing the death of a young woman and injuring her child and another person.

[16] Another tornado, an F2, struck Tallulah, wrecking a self-service laundry and causing roof damage to five homes, resulting in four minor injuries.

[37] 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.

[39] Early on January 21, shortly after midnight CST, another F2 tornado struck the community of James in Shelby County, badly damaging several homes, with three injuries.

[38] Another F2 tornado struck the southwestern side of Orlando, where it removed the roof and wrecked several units of a multi-story apartment complex.

[38] Yet another F3 tornado in the state injured three people as it leveled barns and farmhouses near Pottsboro, where it also moved objects for distances ranging from 100 yd (91 m) to a mile.

[16] An F2 tornado that formed near Geronimo, Oklahoma, was responsible for most of the injuries on this day as it damaged mobile homes and roofs, injuring five people.

[38] Yet a third F2 tornado touched down near Branson in Missouri and leveled several trailers adjourning Table Rock Lake, with four injuries.

An extremely destructive, long-tracked tornado caused the costliest natural disaster in Georgia history up to that time,[22] though officially it only produced F2 damage.

[54] The strongest tornado of the day attained F4 intensity near La Plata, where one home disintegrated and was swept from its foundation, causing one death.

[16] On the latter date, an F2 tornado in the Parnell–Holbrook area in Iowa struck 25 farms in its path, tearing off roofs, leveling several barns, and causing one home to slide and buckle.

[25] A separate F2 tornado damaged several structures, including a café, as it passed over part of the Great Salt Plains Lake and tracked near Medford in Oklahoma, inflicting six injuries.

[25] On May 1, a low-end F2 tornado hit Siloam Springs, Arkansas, toppling several structures, including a broiler facility, and causing four injuries in the area.

[25] Later that day, the only F5 tornado of the year in the U.S. touched down near Valley Mills, Texas, leveling a few barns, with only scant debris left on the foundations.

[25] The next day, May 7, an F3 tornado affected the vicinity of Poplar Bluff, Missouri, where it tipped over boxcars, flattened a barn, and turned a home that stayed on its foundation.

[25] On May 8, a long-tracked F2 tornado traveled almost 30 mi (48.3 km) through the Guntersville–Rainsville area in Alabama, damaging or destroying numerous structures, killing two people, and injuring 12.

Three people were killed when a F1 tornado picked up a 19-foot boat and threw it back in the water before uprooting trees at shore in Cheney Reservoir.