A three-dimensional volume scan of the Nashville tornado-producing supercell. (Matthew Cappucci/GR2 Analyst)
At least 24 are dead and scores more injured after a series of devastating tornadoes plowed through the heart of Nashville and areas to the east early Tuesday. The tornadoes came in the shroud of darkness, deadly freight trains barreling through an otherwise mild spring night. In their wake lay a 50-mile stretch of communities picking up the pieces from the sudden, violent storms.
The Nashville tornadoes in particular produced damage consistent with at least an EF-3 rating on the 0 to 5 Enhanced Fujita scale for tornado intensity, according to the National Weather Service.
The first strip of damage extended from near Nashville to Gordonsville, which radar imagery suggests may have stemmed from one tornado. It appears a different touchdown occurred and caused severe damage in Cookeville. The tornadoes were part of the same tornado family, spawned from the same parent supercell thunderstorm.
[Tornadoes kill at least 22 people, leave trail of destruction in and around Nashville]
The forecast Monday afternoon called for strong storms, but belied the scenes of destruction to come. The National Weather Service’s Storm Prediction Center did include Nashville in its morning outlook as having a “slight risk� of severe weather, with a 2 percent chance of tornadoes within 25 miles of the city. “[The] primary risk appears to be hail,� forecasters wrote, “but locally damaging winds and even a couple of tornadoes would be possible.�
A few severe thunderstorms had trekked through parts of Illinois and Kentucky on Monday evening, with an isolated thunderstorm entering western Tennessee shortly after 10 p.m. The National Weather Service in Nashville wrote that “storm mode looks to become increasingly messy� and called for loose organization after 10 p.m., but forecasters noted that an “isolated tornado� could not be ruled out.
“I’ll be honest with you, we were under a slight risk for severe storms, obviously severe weather wasn’t out of the question, but we did not anticipate a tornado of this magnitude in the middle of the night,� said Mark Rose, a meteorologist at the National Weather Service in Nashville, in an interview.
At 11:02 p.m., the National Weather Service in Memphis — which covers regions in western Tennessee — issued a tornado warning for a rotating thunderstorm, known as a supercell, as it crossed into Benton County. Reports of a possible tornado emerged near Camden, nearly 90 minutes before the supercell thunderstorm arrived in Nashville.
The Storm Prediction Center issued a tornado watch for Nashville at 11:20 p.m. — after most people had probably gone to bed, and too late to be included on some evening weathercasts — in anticipation that the lone supercell could take advantage of an unstable environment over the metropolitan area.
The violent supercell formed south of a warm front that hung around during the evening and overnight in the Tennessee Valley. Temperatures actually increased several degrees before midnight as southerly winds ahead of the storm trucked in moisture-rich air.
Meanwhile, an approaching cold front served as the trigger for severe weather. One persistent supercell became established and dropped tornadoes during its five-hour trek across Tennessee. The storm became nestled within the intersection of the warm and cold fronts, the intertwining air masses contributing to the longevity of the storm.
Baseball-size hail accompanied the storm in Dickson, about 35 miles west-southwest of Nashville. The area remained under a tornado warning until 12:15 a.m. as it trekked east toward Nashville.
The tornado warning was dropped at 12:15 a.m. despite strong rotation occasionally showing up within the lowest levels of the storm.
“We did get some damage reports [earlier], and then we didn’t get any … it looked for a while that the storm had weakened,� Rose said.
[Photos: The scene in Nashville]
But the storm didn’t weaken much. At 12:35 a.m., the rapidly rotating storm entered the western sections of Nashville. The National Weather Service issued a tornado warning.
Immediately, a “debris ball� showed up on radar. That’s telltale evidence that a tornado is on the ground. It results when the radar beam’s signal bounces not off large hail but rather shrapnel and other airborne debris. The tornado appears to have touched down directly over the John C. Tune Airport.
A slice through the storm's radar data shows a “debris ball� at ground level. The tornado's corkscrew updraft high into the storm can be seen. (Matthew Cappucci/GR2 Analyst)
Three minutes later, the National Weather Service warned of a “large and extremely dangerous tornado� in Nashville, calling it a “Particularly Dangerous Situation.�
The tornado passed just north of the Tennessee State Capitol at 12:41 a.m. At that point, it was lofting debris more than 20,000 feet high. Doppler radar detected object with “low correlation coefficient,� plotted in blue, high in the sky. The presence of jagged, oblong, or nonuniform shapes suggests that something aside from raindrops were in the air.
The height to which tornado debris was carried is commensurate with what may be EF-3 tornado strength or greater, with a twister likely producing winds of 160 mph or more. Confirmation of that came Tuesday afternoon from the NWS’ damage survey team, which can take days to complete their full analysis.
A look at “correlation coefficient� on radar shows where irregular shapes, caused by tornadic debris, are detected soaring to a height of 20,000 feet. (Matthew Cappucci/GR2 Analyst)
Just east of the Cumberland River downtown, the tornado crossed the paths taken by both the infamous 1933 and 1998 tornadoes that tore through Nashville.
A three-dimensional volume radar scan reveals the storm’s corkscrew rotating updraft towering high in the sky. A debris ball can be seen at its base on the lowest scan level.
The tornado passed just a couple miles south of the National Weather Service’s radar as it plowed through the Mount Juliet area at 12:54 a.m. It traveled just north of Interstate 40. Insulation and debris landed at the National Weather Service office itself, according to a note on an NWS chat system.
In some of those areas, the tornado preceded any rain — highlighting the importance of heeding any warnings immediately, rather than waiting for rain, hail, lightning or thunder.
The tornado then appears to have crossed directly over Highway 109, just north of the Interstate 40 interchange in Lebanon, impacting the spattering of businesses near where Eastgate Boulevard becomes Leeville Pike. This occurred at 1:03 a.m.
Data also suggests that the south side of Lebanon endured significant damage, with the tornado passing near or over a Walmart Supercenter and the Cedars Square Shopping Center, a major commercial area.
Despite a slightly messier storm structure, the circulation strengthened further to the east of Lebanon as the tornado nicked regions just north of Interstate 40 near Bluebird Road and Highway 141. Based on radar indications, the tornado briefly swallowed the interstate near Pratt’s Orchard & Garden Center.
The circulation then began to weaken and turn slightly to the right, crossing over Interstate 40 at exit 254, where it then proceeded just south of east toward southern Gordonsville. The tornado appears to have lifted southeast of the town between 1:33 and 1:36 a.m.
If confirmed as one continuous vortex, then we may be looking at an hour-long tornado that was on the ground for more than 52 miles. That’s extreme by any standards, but even more impressive considering the time of day — between midnight and 2 a.m.
An approximate path of where Doppler radar analysis revealed the tornadic circulation traveled. (Matthew Cappucci/GR2 Analyst)
This tornado, undoubtedly a long-track tornado, also came from a long-track supercell. Tornado warnings were hoisted intermittently along its passage between 11 p.m. and nearly 4 a.m.
Another tornado from the same supercell occurred in Cookeville, Tenn., around 2 a.m. Some reports suggest more fatalities may have occurred from the Cookeville tornado than the one in Nashville.
Tornadoes are especially dangerous at night. A 2018 study found that nearly half of all tornadoes in Tennessee occurred at night. More than 60 percent of these tornadoes resulted in deaths. Tennessee sees a higher percentage of its tornadoes at night than any other state in the nation.
[Tennessee is state with highest percentage of tornadoes at night, when they’re most deadly]
The twister bears shade of 1998, when an F3 tornado killed one person as it ravaged downtown Nashville on April 16.
It’s a reminder that tornadoes can and do occur in cities. Major metropolitan areas such as Atlanta, Springfield, Mass., Joplin, Mo., Miami, New York City, and even Salt Lake City have been hit in the past 30 years. Dayton, Ohio, Dallas, and just west of Kansas City, Kan., were all hit in just the past year.
[Inside the Southeast tornado swarm that devastated Lee County, Alabama]
Tragically, Tuesday morning’s tornadoes resulted in at least 24 fatalities. The death toll has even surpassed the 23 killed in the tornado event in Lee County, Ala., on March 3, 2019 — exactly one year ago.
It’s also the deadliest Tennessee tornado event since one that claimed more than 30 lives on April 27, 2011, during the Super Outbreak.